IT'S a solar double whammy. Not only does sunlight melt Arctic ice, but it also speeds up the conversion of frozen organic matter into carbon dioxide.
The amount of carbon in dead vegetation preserved in the far northern permafrost is estimated to be twice what the atmosphere holds as CO2. Global warming could allow this plant matter to decompose, releasing either CO2 or methane – both greenhouse gases. The extent of the risk remains uncertain because the release mechanisms are not clear.
Rose Cory at the University of North Carolina at Chapel Hill and her colleagues analysed water from ponds forming on melting permafrost at 27 sites across the Arctic. They found that the amount of CO2 released was 40 per cent higher when the water was exposed to ultraviolet light than when kept dark. This is because UV light, a component of sunlight, raises the respiration rate of soil bacteria and fungi, amplifying the amount of organic matter they break down and the amount of CO2 released.
The thawing Arctic is emerging as a potentially major source of positive feedback that could accelerate global warming beyond existing projections. "Our task now is to quantify how fast this previously frozen carbon may be converted to CO2, so that models can include the process," Cory says.
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BEIJING: China is unlikely to punish troublesome ally North Korea harshly for Tuesday's nuclear test, analysts say, even though Chinese state media had warned the North of a "heavy price" if it went ahead.
There was no immediate official reaction to the test in Beijing -- China is in the middle of its biggest annual holiday, the Lunar New Year.
But after the North's rocket launch in December, China expressed "regret", while repeating calls for calm.
In recent weeks the state-run Global Times has issued strongly-worded editorials urging Beijing to take a tougher line on Pyongyang, saying it would have to pay dearly for another atomic test.
But China has long supported its unpredictable neighbour for fear that instability could bring refugees flooding across the border, a US-led military escalation in the region or even ultimately a unified Korea with a US military presence next door.
"I think that China is very angry about this test," said Stephanie Kleine-Ahlbrandt, Northeast Asia director of the International Crisis Group think tank.
She said she expected "stronger reactions" from the Communist Party's new leader Xi Jinping than his predecessors.
But she added: "We won't necessarily know about any punitive measures implemented by China, and they will not necessarily deter North Korea because China is only willing to go so far. Their main concern is stability in North Korea."
Chinese trade and aid allows the regime in Pyongyang to survive and pursue its nuclear programme.
At once important yet uncontrollable, North Korea poses a similar quandary for China as small-nation allies did for the US during the Cold War, said Wang Dong, a Northeast Asia expert at Peking University.
"You have small allies which are behaving in a very dangerous, aggressive and provocative way, potentially with the danger of driving the US into a conflict that it did not want to get into," he said.
"China is put in a very similar dilemma."
Beijing will probably respond with limited measures coordinated with other nations, perhaps to cut off financial access, Wang said. It would keep any unilateral measures under wraps to avoid antagonising Pyongyang.
In 2006 Beijing quietly reduced the oil supply upon which Pyongyang depends, two months after the regime fired a ballistic missile and one month before it tested its first nuclear bomb.
The move only emerged later when trade data revealed it -- and Beijing subsequently stopped publicising the figures.
"Of course it will not acknowledge that because they do not want to publicly humiliate North Korea," said Wang. "Face is something very much taken into consideration in international relations in East Asia."
Ahead of the blast, US envoy Glyn Davies said the US and China had "achieved a very strong degree of consensus" on North Korea while the head of the UN Security Council said its 15 members were "unified" on the matter.
But China has previously worked to soften international measures. It only agreed to a UN resolution condemning December's long-range rocket launch by Pyongyang after lengthy negotiations in which it opposed stronger sanctions.
It also diluted the UN response to North Korea's second nuclear test in 2009 and was not known to have taken any unilateral measures.
Even decisively punitive measures might fail to dissuade North Korea, which has persisted with its nuclear programme despite years of international isolation.
Pyongyang sees atomic arms as vital to its legitimacy and security, a view that may have been reinforced after the longstanding Kadhafi regime in Libya, which surrendered its nuclear weapons, fell to Western-backed rebels in 2011.
"They've drawn the conclusion that countries that give up their nukes get slammed," said Kleine-Ahlbrandt.
Given Pyongyang's doggedness, she said, Beijing's unwavering support for the regime has generated fierce debate among Chinese policy analysts, with some arguing that the relationship brings more liabilities than benefits.
But China's overriding strategic interest in avoiding instability means its support is likely to endure, said Sarah McDowall, a senior Asia analyst with the consultancy IHS Global Insight.
"Its overarching objective really is to ensure stability in the Korean peninsula," she said.
"The relationship is going to remain strong, and China will continue to take political and economic measures aimed at propping up and supporting the North Korean regime."
NEW: "We believe North Korea conducted its third nuclear test," a South Korean official says
A magnitude 4.9 disturbance takes place in area of previous underground nuclear tests
There is little or no history of natural seismic activity in the area
North Korea said last month it would carry out a third nuclear test
Hong Kong (CNN) -- North Korea appeared to have conducted its third underground nuclear bomb test Tuesday, officials and experts said, as U.S. seismologists reported activity centered near the site of the secretive regime's two previous atomic blasts.
Although North Korea had warned the world of its plans to carry out a new test in a vitriolic statement last month, the move is still likely to rattle the security situation in Northeast Asia as analysts try to determine the power and complexity of the device the North is thought to have detonated.
If confirmed, it would be the first nuclear test under the North's young leader, Kim Jong Un, who appears to be sticking closely to his father's policy of building up the isolated state's military deterrent to keep its foes at bay, shrugging off the resulting international condemnation and sanctions.
It also provided a provocative reminder of a seemingly intractable foreign policy challenge for President Barack Obama ahead of his State of the Union address later Tuesday.
The area around the reported epicenter of the magnitude 4.9 disturbance in northeastern North Korea has little or no history of earthquakes or natural seismic hazards, according to U.S. Geological Survey maps. The disturbance Tuesday took place at a depth of about 1 kilometer, the USGS said.
Officials suspect a nuclear test
Government officials and security analysts had little doubt about the cause of the quake.
"We believe North Korea conducted its third nuclear test," said Kim Min-seok, a spokesman for the South Korean defense ministry. He added that the magnitude of the "artificial tremor" suggested the size of the blast was in the order of 6 to 7 kilotons, more powerful than the North's two prior nuclear tests.
"If we come to a final conclusion that it is a nuclear test," he said, "then we will consult with the international community and respond strongly."
Japanese Chief Cabinet Secretary Yoshihide Suga said that based on past cases, "We believe there is a possibility that North Korea conducted a nuclear test."
There were no initial reports concerning the activity on the North's state-run Korean Central News Agency on Tuesday.
"It's a nuclear test," said Jeffrey Lewis, director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at the Monterey Institute of International Studies. "That magnitude and that location -- it's awfully unlikely it's anything else."
In Washington, a senior administration official said the United States was working to confirm a nuclear test.
The China Earthquake Network Center said on its website that the seismic disturbance in North Korea was a "suspected explosion."
News breaks at a quiet time in Asia
The suspected test took place at a time when several East Asian countries, including China, North Korea's major ally, are observing public holidays for the Lunar New Year, which began Sunday.
It also comes ahead of the birthday on Saturday of Kim Jong Il, the former North Korean leader who died in December 2011 and was succeeded by his son, Kim Jong Un.
North Korea announced last month that it was planning a new nuclear test and more long-range rocket launches, all of which it said were part of a new phase of confrontation with the United States.
It made the threats two days after the United Nations Security Council had approved the broadening of sanctions on the reclusive, Stalinist regime in response to the North's launching of a long-range rocket in December that succeeded in putting a satellite in orbit.
Pyongyang said it carried out the launch for peaceful purposes, but it was widely considered to be a test of ballistic missile technology.
U.S. analysts say North Korea's first bomb test, in October 2006, produced an explosive yield at less than 1 kiloton (1,000 tons) of TNT. A second test in May 2009 is believed to have been about two kilotons, National Intelligence Director James Clapper told a Senate committee in 2012.
By comparison, the bomb the United States dropped on Hiroshima in 1945 was a 15-kiloton device.
In May 2012, North Korea said it had amended its constitution to formally proclaim itself a "nuclear state."
CNN's Jethro Mullen reported and wrote from Hong Kong. CNN's K.J. Kwon in Seoul, South Korea; Yoko Wakatsuki in Tokyo; Dana Ford and Matt Smith in Atlanta, Georgia; and Elise Labott in Washington contributed to this report. Journalist Connie Young in Beijing also contributed reporting.
Several lawmakers are bringing special guests to President Obama's State of the Union address Tuesday night in order to make a statement.
Several lawmakers are bringing guests to help underscore the importance of gun control. More than 20 House Democrats are bringing guests who have been personally affected by gun violence. A bipartisan pair of Arizona lawmakers, meanwhile, will host former Rep. Gabrielle Giffords, D-Ariz., and her husband Mark Kelly.
Other lawmakers are bringing guests tied to issues like immigration and voting rights.
Below is a partial list of officials and the guests they are bringing. CBS News will update the list as more guests are confirmed:
First Lady Michelle Obama:
Lt. Brian Murphy, who was wounded while responding to the Sikh Temple shooting last August in Oak Creek, Wisconsin. He was struck by 15 bullets.
Cleopatra Cowley-Pendleton and Nathaniel Pendleton Sr., parents of 15-year-old Hadiya who was killed in a Chicago park.
Desiline Victor, a 103-year-old Florida woman who waited in line for several hours to vote.
Tim Cook, CEO of Apple.
House Minority Leader Pelosi:
Mother and daughter from Newtown, Conn. The 4th grader sent Pelosi a letter asking for her support to strengthen gun laws in the wake of the Sandy Hook massacre.
Sen. John McCain, R-Ariz., and Rep. Ron Barber, D-Ariz.:
Former Rep. Gabrielle Giffords, D-Ariz., and her husband Mark Kelly
Rep. Steve Stockman, R-Texas:
Musician and gun advocate Ted Nugent
Sens. Richard Blumenthal, D-Conn., and Chris Murphy, D-Conn.:
First Selectwoman Pat Llodra, a Republican and the Chief Executive Officer of Newtown
Newtown Detectives Jason Frank and Dan McAnaspie, two of several first responders who rushed to Sandy Hook Elementary School on the day of the tragedy
Rep. Luis Gutierrez, D-Ill.:
Undocumented immigrant Gabino Sanchez. The South Carolina husband and father of two U.S. citizen children is fighting deportation. Sanchez entered the country when he was 15 years old and has been working and living peacefully in the U.S. ever since.
Sen. Dianne Feinstein, D-Calif.:
Josh Stepakoff, who in 1999 was shot at the North Valley Jewish Community Center in Granada Hills, Calif. Stepakoff, now 20, is a student at California State University Northridge.
Sen. Frank Lautenberg, D-N.J.:
Matt Gross, a New Jersey native who was shot in the head in 1997, at the age of 27. Gross was one of several victims wounded during a shooting attack on the observation deck of the Empire State Building.
More House Democrats bringing guests affected by gun violence:
North Korea says it has successfully tested a miniaturized nuclear device Tuesday, according to state media.
A large tremor measured at magnitude 4.9 was detected in North Korea and governments in the region scrambled to determine whether it was a nuclear test that the North Korean regime has vowed to carry out despite international protests.
Official state media said the test was conducted in a safe manner and is aimed at coping with "outrageous" U.S. hostility that "violently" undermines the North's peaceful, sovereign rights to launch satellites. Unlike previous tests, North Korea used a powerful explosive nuclear bomb that is smaller and lighter, state media reported.
Japan's prime minister has called an urgent security meeting, according to chief government spokesman Yoshihide Suga, and South Korea raised its military alert level, the AP reported.
Suspicions were aroused when the U.S. Geological Survey said it had detected a magnitude 4.9 earthquake Tuesday in North Korea.
The Comprehensive Test Ban Treaty Organization told ABC News, "We confirm that a suspicious seismic event has taken place in North Korea."
"The event shows clear explosion-like characteristics and its location is roughly congruent with the 2006 and 2009 DPRK (North Korea) nuclear tests," said Tibor Toth, executive secretary of the organization.
North Korea Threatens More Nuclear Tests, Warns U.S. Watch Video
"If confirmed as a nuclear test, this act would constitute a clear threat to international peace and security, and challenges efforts made to strengthen global nuclear disarmament and non-proliferation," Toth said in a statement on the organization's web site.
Kim Min-seok, a South Korean Defense Ministry spokesman, told reporters that North Korea informed United States and China that it intended to carry out another nuclear test, according to the AP. But U.S. officials did not respond to calls from ABC News Monday night.
The seismic force measured 10 kilotons, according to Min-seok.
"Now that's an absolutely huge explosion by conventional terms. It's a smallish, but not tiny explosion by nuclear terms. It's about two-thirds the size of the bomb that the U.S. dropped on Hiroshima," James Acton, a Senior Associate at the Carnegie Endowment for International Peace, told ABC News.
North Korea threatened in January to carry out a "higher-level" test following the successful Dec. 12 launch of a long range rocket. At the time, North Korea's leader Kim Jong-Un said his country's weapons tests were specifically targeting the United States.
The suspicious tremor comes just hours before President Obama is to give the State of the Union address, and it marks the first diplomatic test in the region for new Secretary of State John Kerry.
Also, South Korea's new president, Park Geun-hye, is scheduled to be sworn in on Feb. 25. One of North Korea's biggest holidays, Kim Jong-il's birthday, falls on Feb. 16.
China, North Korea's main ally in the region, has warned North Korea it would cut back severely needed food assistance if it carried out a test. Each year China donates approximately half of the food North Korea lacks to feed its people and half of all oil the country consumes.
Both of North Korea's previous tests used a plutonium-based method for making bomb fuel. The first was deemed a failure, the second only slightly less so. If the most recent test used HEU (highly enriched uranium), a far more difficult-to-detect method of producing bomb fuel, it would be a significant and worrisome step forward for North Korea's weapons program.
The virus used in the vaccine that helped eradicate smallpox is now working its magic on liver cancer. A genetically engineered version of the vaccinia virus has trebled the average survival time of people with a severe form of liver cancer, with only mild, flu-like side effects.
Thirty people with hepatocellular carcinoma received three doses of the modified virus – code-named JX-594 – directly into their liver tumour over one month. Half the volunteers received a low dose of the virus, the other half a high dose. Members of the low and high-dose groups subsequently survived for, on average, 6.7 and 14.1 months respectively. By contrast, trials several years ago showed that sorafenib, the best existing medication for this cancer, prolonged life by only three months.
Two of the patients on the highest viral dose were still alive more than two years after the treatment. "It's a very substantial survival benefit," says Laurent Fischer, president of Jennerex, the company in San Francisco developing the treatment under the trade name Pexa-Vec.
Besides shrinking the primary tumour, the virus was able to spread to and shrink any secondary tumours outside the liver. "Some tumours disappeared completely, and most showed partial destruction on MRI scans," says David Kirn, head of the study at Jennerex. Moreover, the destruction was equally dramatic in the primary and secondary tumours.
"This clinical trial is an exciting step forward to help find a new way of treating cancers," says Alan Melcher of the University of Leeds, UK, who was not involved in the study. "It helps demonstrate the cancer-fighting potential of viruses, which have relatively few side effects compared with traditional chemo or radiotherapy," he says. "If it proves effective in larger trials, it could be available to patients within five years."
The fact that the virus appears able to spread to secondary tumours suggests that simply injecting the virus into the bloodstream may be effective. A trial to compare this treatment with injecting the virus directly into a tumour is under way.
Targeted at cancer
The virus has had a gene coding for an enzyme called thymidine kinase snipped out. The enzyme enables the virus to recognise and infect dividing cells. By removing the gene, the virus's developers have reduced the likelihood of healthy dividing cells being infected.
Instead, the virus exclusively attacks cancerous tissue, by targeting two genes that have increased activity in tumour cells. One genes is associated with an epidermal growth factor receptor, which stimulates the cancer to grow. The other is associated with a vascular endothelial growth factor, which enables the cancer to recruit its own blood supply. The virus reduces the activity of both genes, causing the infected cancer cell to wither and die.
What's more, the virus carries extra genes to prod the body's own immune system into action against the cancer. One produces granulocyte colony stimulating factor, a protein that encourages production of extra white blood cells at sites of infection. The other produces a protein not naturally found in humans, called Lac-Z, that earmarks infected cells for destruction.
Fischer says that to date, more than 200 people have received the virus, which has also shown promise against other types of cancer, including those of the kidney and skin. But he warns that not everyone sees a benefit. "We know why patients respond, but not why they don't," he says.
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SYDNEY: Global technology giants Microsoft, Apple and Adobe were on Monday ordered to appear before a pricing inquiry examining the often-higher cost of tech goods in Australia compared with other economies.
The lower house committee holding the probe, which was launched last May, said it had summoned the trio to appear at a public hearing next month to explain why Australian customers paid more for the same products.
"The committee is looking at the impacts of prices charged to Australian consumers for IT products," it said in a statement.
"Australian consumers often pay much higher prices for hardware and software than people in other countries."
The inquiry was set up to examine claims by consumer advocacy groups of price discrimination for Australians on technology, with music, games, software, and gaming and computer hardware costing substantially more than elsewhere.
According to consumer lobby group Choice, Australians pay on average 73 percent more on iTunes downloads than the United States, 69 percent more on computer products and a staggering 232 percent more on PC game downloads.
Office software was on average 34 percent more expensive in Australia when compared with the United States, Choice said in its submission to the inquiry, with hardware coming in at 41 percent more expensive.
One software package was A$8,665 (US$8,939) more expensive to buy in Australia than the United States -- a gap that Choice described as "particularly unreasonable".
"For this amount, it would be cheaper to employ someone for 46 hours at the price of $21.30 per hour and fly them to the US and back at your expense -- twice," Choice said.
Choice only did comparisons to the United States and Britain; the inquiry is examining discrepancies with these countries as well as with Asia-Pacific economies.
Apple and Microsoft have both made their own submissions to the committee, arguing that prices differed across jurisdictions due to a range of factors including freight, local taxes and duties and foreign exchange rates.
The Australian Information Industry Association, which represents Adobe and other major ICT firms, has submitted to the committee that the "costs of doing business in Australia are higher than in many other countries".
It pointed to retail rent costs and high wages as some of the main factors behind business costs in Australia being "5-10 percent higher than any other country... and these costs are passed onto consumers".
Apple and Microsoft both declined to comment when contacted by AFP while Adobe said it would "cooperate with the committee as we have done since the inquiry began".
NEWPORT, R.I. Travel eased and life slowly returned to normal for most New Englanders after a massive blizzard, but many remained without power in cold and darkened homes and a forecast of rain brought a new worry: Weight piling up dangerously on roofs already burdened by heavy snow.
61 Photos
Powerful blizzard descends on Northeast
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Northeast sees record snow fall
The storm that slammed into the region with up to 3 feet of snow was blamed for at least 14 deaths in the Northeast and Canada, and brought some of the highest accumulations ever recorded. Still, coastal areas were largely spared catastrophic damage despite being lashed by strong waves and hurricane-force wind gusts at the height of the storm.
President Barack Obama declared a state of emergency for Connecticut, allowing federal aid to be used in recovery, and utilities in some hard-hit New England states predicted that the storm could leave some customers in the dark for days.
CBS News correspondent Miguel Bojorquez reports that Hamden, Conn., about 80 miles from New York City, experienced the deepest snow: 40 inches. The blizzard had dumped five inches of snow per hour.
Hundreds of people, their homes without heat or electricity, were forced to take refuge in emergency shelters set up in schools or other places.
"For all the complaining everyone does, people really came through," said Rich Dinsmore, 65, of Newport, R.I., who was staying at a Red Cross shelter set up in a middle school in Middletown after the power went out in his home on Friday.
Dinsmore, who has emphysema, was first brought by ambulance to a hospital after the medical equipment he relies on failed when the power went out and he had difficulty breathing.
"The police, the fire department, the state, the Red Cross, the volunteers, it really worked well," said the retired radio broadcaster and Army veteran.
Utility crews, some brought in from as far away as Georgia, Oklahoma and Quebec, raced to restore power to more than 300,000 customers -- down from 650,000 in eight states at the height of the storm. In hardest-hit Massachusetts, where some 234,000 customers remained without power on Sunday, officials said some of the outages might linger until Tuesday.
Driving bans were lifted and flights resumed at major airports in the region that had closed during the storm, though many flights were still canceled Sunday.
Boston recorded 24.9 inches of snow, making it the fifth-largest storm in the city since records were kept.
On eastern Long Island, which was slammed with as much as 30 inches of snow, hundreds of snowplows and other heavy equipment were sent in Sunday to clear ice- and drift-covered highways where hundreds of people and cars were abandoned during the height of the storm.
More than a third of all the state's snow-removal equipment was sent to the area, Gov. Andrew Cuomo said, including more than 400 plow trucks and more than 100 snow blowers, loaders and backhoes.
Play Video
Snow leaves Long Island Expressway commuters stranded
Play Video
Mass. town powerless after record snow storm
The National Weather Service was forecasting rain and warmer temperatures in the region on Monday -- which could begin melting some snow but also add considerable weight to snow already piled on roofs, posing the danger of collapse. Of greatest concern were flat or gently-sloped roofs and officials said people should try to clear them -- but only if they could do so safely.
"We don't recommend that people, unless they're young and experienced, go up on roofs," said Peter Judge, spokesman for the Massachusetts Emergency Management Agency.
Officials also continued to warn of carbon monoxide dangers in the wake of the storm.
In Boston, two people died Saturday after being overcome by carbon monoxide while sitting in running cars, including a teenager who went into the family car to stay warm while his father shoveled snow. The boy's name was not made public. In a third incident, two children were hospitalized but expected to recover.
A fire department spokesman said in each case, the tailpipes of the cars were clogged by snow.
Authorities also reminded homeowners to clear snow from heating vents to prevent carbon monoxide from seeping back into houses.
In Maine, the Penobscot County Sheriff's office said it recovered the body of a 75-year-old man who died after the pickup he was driving struck a tree and plunged into the Penobscot River during the storm. Investigators said Gerald Crommett apparently became disoriented while driving in the blinding snow.
Christopher Mahood, 23, of Germantown, N.Y., died after his tractor went off his driveway while he was plowing snow Friday night and rolled down a 15-foot embankment.
A Northridge, Calif., home improvement store was evacuated tonight because of a possible sighting of suspected cop-killer Christopher Dorner, just hours after police announced a $1 million reward for information leading to his arrest.
As helicopters hovered overhead and a command center was established, police searched the Lowe's store and eventually told shoppers they could leave, but could not take their cars out of the parking lot.
LAPD spokesman Gus Villanueva said the major response to the possible sighting was a precaution, but couldn't say whether Dorner was in the area.
The announcement of the $1 million reward today came as authorities in Big Bear, Calif., scaled back their search for Dorner, the disgruntled ex-cop who is suspected in three revenge killings.
"This is the largest local reward ever offered, to our knowledge," Los Angeles Police Chief Charlie Beck said at a news conference today. "This is an act of domestic terrorism. This is a man who has targeted those that we entrust to protect the public. His actions cannot go unanswered."
The money for the reward was pooled by businesses, government, local law enforcement leaders and individual donors, Beck said.
PHOTOS: Former LAPD Officer Suspected in Shootings
The reward comes on the fourth day of a manhunt for Dorner, who has left Southern California on edge after he allegedly went on a killing spree last week to avenge his firing from the police force. Dorner outlined his grievances in a 6,000 word so-called "manifesto" and said he will keep killing until the truth is known about his case.
Irvine Police Department/AP Photo
Manhunt for Alleged Cop Killer Heads to California Mountains Watch Video
Christopher Dorner Search: Officials Search for Ex-officer in the Mountains Watch Video
Dorner's threats have prompted the LAPD to provide more than 50 law enforcement families with security and surveillance detail, Beck said.
Authorities are chasing leads, however they declined to say where in order to not impede the investigation.
Dorner's burned-out truck was found Thursday near Big Bear Lake, a popular skiing destination located 80 miles northeast of Los Angeles.
Investigators found two AR-15 assault rifles in the burned-out truck Dorner abandoned, sources told ABC News.
The truck had a broken axle, which may be the reason he decided to set fire to it, the police sources said.
Full Coverage: Christopher Jordan Dorner
Officers have spent the past couple of days going door-to-door and searching vacant cabins. The manhunt was scaled back to 25 officers and one helicopter in the resort town today, according to the San Bernadino Sheriff's Office.
On Saturday, Beck announced he would reopen the investigation into Dorner's firing but said the decision was not made to "appease" the fugitive ex-cop.
"I feel we need to also publicly address Dorner's allegations regarding his termination of employment, and to do so I have directed our Professionals Standards Bureau and my Special Assistant for Constitutional Policing to completely review the Dorner complaint of 2007; To include a re-examination of all evidence and a re-interview of witnesses," Beck said. "We will also investigate any allegations made in his manifesto which were not included in his original complaint."
Quan's father, Randal Quan, was a retired captain with the LAPD and attorney who represented Dorner before a police review board that led to Dorner's dismissal from the force in 2008.
On Wednesday, after Dorner was identified as a suspect in the double murder, police believe he ambushed two Riverside police officers, killing one and wounding the other.
The next day, Randal Quan reported he received a taunting call from a man claiming to be Dorner who told him that he "should have done a better job of protecting his daughter," according to court documents documents.
Anyone with information leading to the arrest of Christopher Dorner is asked to call the LAPD task force at 213-486-6860.
ABC News' Dean Schabner, Jack Date, Pierre Thomas, Jason Ryan and Clayton Sandell and The Associated Press contributed to this report.
