Massive reward offer for Christopher Dorner

Updated 9:58 p.m. ET

BIG BEAR LAKE, Calif. Authorities are offering a $1 million reward for information leading to the arrest of Christopher Dorner, the former Los Angeles police officer suspected in three killings who is the subject of a manhunt in Southern California.

L.A. Police chief Charlie Beck said time was of the essence in making the reward offer.

"Every day that Dorner is loose, the likelihood of an attack on either a uniformed police officer or a family of a police officer, is likely. That's why we rush to make this offer," Beck said.

L.A. Mayor Antonio Villaraigosa announced the reward at a news conference at LAPD headquarters Sunday. The L.A. mayor said it is only a question of time before Dorner is caught, and that the confidence of officials is "unshaken," despite it being seven days since the killings began.

"Our dedication to catch this killer remains steadfast," Villaraigosa said. "We will not tolerate this reign of terror."

Riverside City Mayor Rusty Bailey said the reward was gathered from a combination of public and private groups, and that gathering it was "easy," given the extreme local interest in the situation.

Police evacuated a Los Angeles Lowes Thursday afternoon after a caller said they had seen someone resembling Dorner. But police have not confirmed whether the call was legitimate.

"The situation is ongoing, and we have resources out there checking out the reports," Gus Villanueva, a detective with the LAPD, told KCBS-TV .

Some 80 miles to the east, SWAT teams with bloodhounds and helicopter support continued to scour snow-covered mountains near Big Bear, where the 33-year-old fugitive's charred pickup truck was discovered Thursday. There have been no sightings of Dorner himself in Big Bear, although surveillance footage outside an auto store in National City, south of San Diego, caught him dumping bullets and other potential evidence last Monday, CBS affiliate KFMB reports.

KCBS in Los Angeles reports about 50 law enforcement officers began the search combing the snow-capped terrain this weekend with the assistance of two heat-seeking helicopters. By Sunday, 25 officers and a single helicopter were looking for clues in the forest and going door-to-door at some 600 cabins in the San Bernardino mountains.

On Saturday, LAPD announced it had formed a task force with the sole mission of finding Dorner, KFMB reports. The task force consists of several law enforcement agencies across Southern California.

Authorities say Dorner has vowed revenge against several former LAPD colleagues whom he blames for ending his career.

Earlier, Police Chief Beck announced officials will re-examine the allegations by Dorner that his law enforcement career was undone by racist colleagues. While he promised to hear out Dorner if he surrenders, Beck stressed that he was ordering a review of his 2007 case because he takes the allegation of racism in his department seriously.

"I do this not to appease a murderer. I do it to reassure the public that their police department is transparent and fair in all the things we do," the chief said in a statement.

At Sunday's press conference, Villaigrosa and Beck bristled at suggestions that the police department was somehow responsible Dorner's behavior. Beck said many things go into making an individual, and that Dorner likely had problems predating his experience as a police officer.

In his online manifesto, Dorner vowed to use "every bit of small arms training, demolition, ordnance and survival training I've been given" to bring "warfare" to the LAPD and its families.

Dorner served in the Navy, earning a rifle marksman ribbon and a pistol expert medal. He was assigned to a naval undersea warfare unit and various aviation training units, according to military records. He took leave from the LAPD for a six-month deployment to Bahrain in 2006 and 2007.

The flight training that he received in the Navy prompted the Transportation Security Administration to issue an alert, warning the general aviation community to be on the lookout for Dorner. The extent of his potential flying skills wasn't known, the bulletin said.

Feb. 1 was his last day with the Navy and also the day CNN's Anderson Cooper received a package that contained a note on it that read, in part, "I never lied." A coin riddled with bullet holes that former Chief William Bratton gave out as a souvenir was also in the package.

Police said it was a sign of planning by Dorner before the killing began.

On Feb. 3, police say Dorner shot and killed a couple in a parking garage at their condominium in Irvine. The woman was the daughter of a retired police captain who had represented Dorner in the disciplinary proceedings that led to his firing.

Dorner wrote in his manifesto that he believed the retired captain had represented the interests of the department over his.

Hours after authorities identified Dorner as a suspect in the double murder, police believe Dorner shot and grazed an LAPD officer in Corona and then used a rifle to ambush two Riverside police officers early Thursday, killing one and wounding the other. A funeral for Officer Michael Crain, an 11 year veteran, was scheduled for Wednesday.

The crime spree spanned across a wide swath of Southern California, prompting several police agencies, including the FBI and US Marshall Service, to form a joint investigative task force.