UPDATED: Renegade Ex-Cop Once Lived in Cerritos, Local Sheriff's Stations on Heightened Alert

Christopher Jordan Dorner, the fired Los Angeles Police Department officer wanted for the revenge slayings of a college basketball coach and her fiance in Irvine, as well as the shooting death of a Riverside police officer and wounding of two others, once lived in Cerritos, according to his online manifesto. 

Dorner, 33, posted a multi-page manifesto online Monday, saying he didn't mind dying because he already died when he was fired from the LAPD, according to law enforcement officials. He wrote that it had been his life's ambition to be an LAPD officer since he served in the Explorer program.

In his lengthy online writings, Dorner implores the media to investigate every location he resided in growing up and to find any incidents where he was accused of being a bully. Among the locations listed is the city of Cerritos and La Palma. His last known address is listed in the 4900 block of Sharon Drive in La Palma.

His online post also states that he was a first grade student at Norwalk Christian elementary school in Norwalk, where he experienced his first incident of racism. 

An excerpt of his manifesto states:

"My first recollection of racism was in the first grade at Norwalk Christian elementary school in Norwalk, CA. A fellow student, Jim Armstrong if I can recall, called me a nigger on the playground. My response was swift and non-lethal. I struck him fast and hard with a punch an kick. He cried and reported it to a teacher. The teacher reported it to the principal. The principal swatted Jim for using a derogatory word toward me. He then for some unknown reason swatted me for striking Jim in response to him calling me a nigger."

Cerritos and Lakewood Sheriff's Stations on Heightened Alert

As the Southland manhunt for Dorner continues, local law enforcement agencies have also been placed on heightened alert. 

In the city of Cerritos, Lt. Richard Harpham of the Cerritos Sheriff's Station said that they are "taking necessary precautions."

"We're doing what we feel needs to be done," Harpham said, declining to elaborate on the specifics for safety reasons. "All of Southern California is on eggshells from here to San Diego ... we advise that everyone just watch the news and get updates."

In the cities of Artesia, Bellflower, Paramount, Hawaiian Gardens and Lakewood -- all of which are patrolled by the Lakewood Sheriff's Station -- Sgt. Daniel Gillespie told Patch that officer safety has been increased.

"We've combined patrol units," he said, adding that deputies usually go out on single-man patrol units but are now going out in pairs to provide "more officer safety."

Timeline of Events that Led to Manhunt

Christopher Jordan Dorner, 33, was identified Wednesday night as a suspect in the slayings of 28-year-old Monica Quan and her fiance, 27-year-old Keith Lawrence, who were found shot to death at 9:10 p.m. Sunday in a parked car at 2100 Scholarship in Irvine. They were inside Lawrence's Kia, which was parked at the top of the five-story parking structure for the building where they lived.

According to police, Quan was the daughter of a retired LAPD captain who represented Dorner at the Board of Rights hearing that led to his firing, and the killings were carried out in an act of revenge outlined in a lengthy manifesto Dorner posted online -- blaming Quan's father for losing his job.

As police fanned out across the Southland, two LAPD officers who were in Corona around 1:20 a.m. Thursday en route to protecting someone mentioned in Dorner's manifesto were approached by a resident who reported seeing a person matching Dorner's description.

"A citizen approached the officers and directed them to a vehicle that matched that of Christopher Dorner's metallic gray Nissan Titan Pickup truck," according to an LAPD statement. The officers saw someone in the truck resembling Dorner, the truck took off and the officers followed it as it entered I-15, according to police.

"The suspect then opened fire on the officers while they were in their vehicle," police said. The LAPD officers fired back, but "it is unknown if the suspect was injured during the shooting."

One officer suffered a minor graze wound to the head in the shooting near Interstate 15 and Magnolia Avenue. The other was not injured. Dorner was described as wearing camouflage fatigues and using a shoulder-held weapon during the Corona shootout.

About 20 minutes later, Dorner is believed to have ambushed two Riverside officers while they were stopped at a red light at Magnolia and Arlington avenues, according to Riverside police Lt. Guy Toussaint, adding that the two were on "routine patrol" and were not searching for Dorner at the time.

One of the officers -- a 34-year-old, 11-year veteran of the force -- was killed. The other Riverside officer, who is 27 years old, underwent surgery and is expected to fully recover, Riverside police Chief Sergio Diaz said.

Later Thursday, the truck belonging to Christopher Jordan Dorner was found burning just off a forest road in Big Bear. That discovery led to a door-to-door search of the area, three law enforcement helicopters circling the area above, the lockdown of Big Bear-area schools and closure of the Bear Mountain ski resort.

Suspect Description

Dorner is black, 6 feet tall and weighs 270 pounds. He has been driving a gray 2005 Nissan Titan pickup, California license plate 7X03191, Maggard said. At a briefing this morning, police said Dorner apparently switched license plates, possibly to a plate with the following number: 8D83987.

Anyone encountering Dorner should consider him "armed and extremely dangerous" and should not approach or try contacting him but instead call 911 immediately, police said. A tip line has been established, (949) 724-7192. People can also call Riverside police at (951) 787-7911.

SWAT Sent to Protect Those Mentioned in Online Manifesto

In Dorner's multi-page manifesto, he blamed Quan for his firing.

"I never had the opportunity to have a family of my own ... (so) I am terminating yours," Dorner wrote to Randy Quan.

The LAPD's elite Metropolitan squad was sent to protect people mentioned in Dorner's manifesto. Their names were not released.

The LAPD issued a statement Wednesday saying it was taking the threats "very seriously," implementing "all measures possible to ensure the safety of our LAPD personnel, their families and the Los Angeles community, and will continue to do so until Dorner is apprehended and all threats have been abated."

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