LAPD investigating hundreds of tips in manhunt for fugitive ex-officer Christopher Dorner

Los Angeles authorities are investigating more than 600 tips after announcing a $1 million reward Sunday for information leading to the arrest of a fugitive ex-cop wanted in the murders of three people.

The trail for 33-year-old Christopher Dorner went cold Thursday after authorities found Dorner's burned-out pickup truck near the California ski resort town of Big Bear in the San Bernardino Mountains. Police have since said they discovered weapons and camping gear inside the vehicle.

The search scaled down as the weekend went on, but a helicopter with heat-seeking technology scanned the area as two dozen officers went back to some of the 600 cabins they earlier visited door to door.

LAPD Chief Charlie Beck said despite the dwindling search, there was not another area that appeared more likely than Big Bear where Dorner might be, saying the suspect's chances to plan beforehand may have helped him remain elusive.

"We have nothing currently better, Beck said at Sunday's news conference.

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Riverside County District Attorney Paul Zellerbach said Monday that Dorner has been charged with murdering a Riverside police officer and special circumstances that could bring the death penalty.

Zellerbach said Dorner is also charged with the attempted murder of another Riverside officer and two LAPD officers.

The charges announced Monday do not involve two other people Dorner is suspected of killing in Orange County.

Schools in Big Bear reopened Monday with tightened security measures and additional law enforcement after they were locked down during the manhunt, district officials told the Los Angeles Times. Classes at the schools were canceled Friday.

Los Angeles Police Department Lt. Andy Neiman said at a Monday morning media briefing that authorities have been in contact with Dorner’s family, and are hoping that the $1 million reward will lead to Dorner’s arrest. Neiman said the manhunt has been a “substantial cost to the city and taxpayers,” the Los Angeles Times reports.

Los Angeles Mayor Antonio Villaraigosa announced the reward at a news conference Sunday alongside police chiefs and mayors from Irvine and Riverside.

“This search is not a matter of if, but a matter of when," he said. "I want Chris Dorner to know that.”

After the announcement, on Sunday evening, police evacuated a Los Angeles home improvement store after one caller said they had seen someone resembling Dorner.

But authorities searched for hours, finding no evidence that Dorner was there or had been there, Los Angeles police spokesman Gus Villanueva said.

Surveillance video from a Southern California sporting goods store shows Dorner purchasing scuba equipment two days before he started his killing spree, according to a TMZ report.

The video shows Dorner carrying in two scuba tanks, which were refilled with oxygen, sources told TMZ. He is shown carrying a third scuba tank and paying for the equipment with cash before leaving the store.

The high-profile case began last Sunday, when Monica Quan and her fiance were found shot dead in Irvine.

Police are looking into a taunting phone call to Quan’s father as part of the investigation of the deaths.

Two law enforcement officers who requested anonymity because of the ongoing investigation told The Associated Press they are trying to determine whether Dorner made the call telling retired police Capt. Randal Quan that he should have done a better job protecting his daughter.

Things escalated Thursday when police say Dorner got into a shootout with police in Corona, grazing an LAPD officer's head with a bullet before escaping. Authorities believe he then used a rifle to ambush two Riverside police officers, killing one and seriously wounding the other.

Police had withheld the names of victims both living and dead because of fears of Dorner targeting their families, but on Sunday the Riverside Police Department released the name of the officer killed, 34-year-old ex-Marine and 11-year department veteran Michael Crain.

The Anaheim native and father of two will be buried at Riverside National Cemetery on Wednesday.

Riverside Police Chief Sergio Diaz said police had hoped Dorner would be in custody by now, but they decided to proceed with the identification and public memorial.

"We're not going to fail our officer and our hero," Diaz said Sunday. "We're going to bury him."

After days without resolution, Dorner's fugitive status has been causing concern among some and downright fear among others in Irvine, an upscale community that the FBI consistently ranks among the safest cities in the U.S.

"If he did come around this corner, what could happen? We're in the crossfire, with the cops right there," said Irvine resident Joe Palacio, who lives down the street from the home surrounded by authorities protecting a police captain mentioned in a manifesto Dorner posted online.

"I do think about where I would put my family," he said. "Would we call 911? Would we hide in the closet?"

The neighborhood has been flooded with authorities since Wednesday. Residents have seen police helicopters circle and cruisers stake out schools. Some have responded by keeping their children home. Others no longer walk their dogs at night.

With little apparent evidence pointing to Dorner's whereabouts, worrisome questions emerged: How long could the intense search be sustained? And, if Dorner continues to evade capture, how do authorities protect dozens of former police colleagues whom he has publicly targeted?

LAPD Cmdr. Andrew Smith said the department has deployed 50 protection details to guard officers and their families who are deemed targets in Dorner's manifesto.

"It can't be one guy with a gun in a living room," Smith said, suggesting that more officers would be necessary to keep families safe.

The department, however, is looking for alternatives if the search for Dorner stretches on, whether it's reducing the numbers of officers or something else, he said.

There are no plans to reduce protections until Dorner is in custody, Los Angeles police Sgt. Rudy Lopez said.

As long as Dorner's whereabouts are unknown, the police department must provide protection to those named in his rant, said Chuck Drago, a Florida-based police consultant.

"We realize it costs money and it gets expensive, but this is as clear of a threat as you can get," he said. "We know that if he's able to get to these targets then he's probably able to hurt them. The money is always an issue but not when it's somebody's life at stake."

The Associated Press contributed to this report.

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