More than 100 police officers headed into the San Bernardino Mountains today searching for suspected cop-killer Christopher Dorner, a former LAPD officer who has vowed "warfare" against the department.
The search was temporarily halted Friday due to blizzard conditions in the area, but after a foot of snow fell overnight, officers were searching hundreds of cabins in the Big Bear Lake today and were using helicopters with thermal imaging technology to find Dorner.
"We're going to continue searching until we find he either left the mountain or we find him, one or the other," San Bernardino, Calif., County Sheriff John McMahon told reporters.
On Thursday, Dorner's burned pick-up truck was found in the Big Bear area, prompting a lockdown of local schools and the temporary shutdown of the Bear Ski Resort. However, footprints initially thought to be Dorner's were determined to actually be tracks from a cross country skier.
Officials also searched property owned by Dorner's mother in nearby Arrowbear, but they found no sign of Dorner there.
"Unless he is an expert in living in the California mountains in this time of year, he is going to be hurting," said former Navy SEAL Clint Sparks, who now works in tactical training and security. "Cold is a huge stress factor. ... Not everybody is survivor-man."
Police released the last known pictures of Dorner on Friday. The photos were taken two weeks ago from a surveillance camera in Orange County, close to where his first two victims were found.
The 33-year-old former Los Angeles police officer and Navy reservist sparked a region-wide manhunt after allegedly shooting and killing a couple in Irvine, Calif. The woman killed in the shooting was the daughter of former Los Angeles Police Captain Randy Quan, who represented Dorner in disciplinary hearings that ended with Dorner being fired.
Dorner also released an angry "manifesto" that warned of coming violence towards cops and listed extensive grievances with the LAPD.
"Your lack of ethics and conspiring to wrong a just individual are over. Suppressing the truth will lead to deadly consequences for you and your family," Dorner wrote in his manifesto.
On Thursday Dorner is believed to have opened fire on two officers, killing one.
The shootings and manifesto have put the LAPD on edge. Motorcycle officers were ordered off their bikes and heavily armed guards were stationed at the LAPD headquarters.
Additionally 40 people listed on the manifesto as targets were given police protection.
In his manifesto Dorner vowed to utilize "every bit of small arms training, demolition, ordnance and survival training I've been given" to bring "warfare" to the LAPD and its families.
"He has a great deal of training and experience in using both offensive and defensive tactics," said Justin Gombos, who served with Dorner in the military.
Dorner is believed to be heavily armed, possibly with a powerful .50 caliber rifle that can pierce bullet-proof vests. His knowledge of police tactics has law enforcement officials "deeply concerned" according to ABC News sources.
"If someone's got background in law enforcement, they've trained in tactics, they're going to have the knowledge and ability to predict our actions more than somebody that hasn't," Mike Parker, a captain with the L.A. County Sheriff's Department told ABCNews.com affiliate KABC-TV.
While police are searching the mountains for Dorner, yesterday they executed a search warrant at his mother's home in La Palma, Calif. Police were seen taking paper bags apparently filled with evidence out of her home, while she and Dorner's sister sat inside.
Jake Plambeck, a neighbor of Dorner's mother, says he was surprised by the events.
"It's a shame to see a nice guy turn a bad corner," Plambeck told ABCNews.com affiliate KABC-TV.
Jamie Usera, from Salem, Ore., who befriended Dorner when they were football teammates at Southern Utah University, said he introduced Dorner to the outdoors through hunting and other activities.
"Of all the people I hung out with in college, he is the last guy I would have expected to be in this kind of situation," Usera, who had lost touch with Dorner in recent years, told the Los Angeles Times.
Court documents obtained by The Associated Press on Friday show an ex-girlfriend of Dorner's called him "severely emotionally and mentally disturbed" after the two split in 2006.
Last Friday was Dorner's last day as a Navy reservist. It was also the day that CNN's Anderson Cooper learned he had received a package allegedly from Dorner, which claimed he "never lied" and featured a bullet ridden coin he had received from Los Angeles Police Chief William Bratton.
Police described Dorner as black, 6-feet tall and weighing 270 pounds. He has black hair and brown eyes.