Officers were at the La Palma, Calif., home of Christopher Dorner's mother Friday afternoon.
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Court Docs Reveal Clues Into Dorner's Past
In 2009, ex-LAPD Officer Christopher Dorner sued the the department to get his job back, but failed. Some experts think it was that failure to get reinstated that sent Dorner over the edge. Court records from his lawsuit with the LAPD reveal more about his mindset. Joel Grover reports for the NBC4 News at 5 p.m. on Feb. 7, 2013.
Aerial video showed officers in protective gear outside the single-family house, one of several locations investigators have visited since ex-Los Angeles Police Department officer Christopher Dorner was accused in the Feb. 3 slayings of a couple in Irvine and Thursday morning's slaying of a Riverside police officer.
Irvine and La Palma police and U.S. Marshals Service officials were at the location in La Palma, Calif., a small Orange County city about 20 miles southeast of downtown Los Angeles.
They removed many brown paper bags of evidence from the home after serving the search warrant at about noon.
"At this point, we're looking for any evidence that would lead us to Dorner's whereabouts or anything in connection with the crimes that he is alleged to have committed," said Irvine Police Lt. Bill Whalen.
An Orange County Regional Computer Forensic Laboratory unit also was at the home in the 4900 block of Sharon Drive, in a residential neighborhood.
Dorner's mother and sister were at the home and were cooperating, officials said.
Dorner, who was fired from the LAPD in 2008, outlined plans to kill law enforcement officers and their family members in an 11,400-word document posted online. In the document, Dorner addressed his reporting of a fellow officer for excessive use of force, and stated he wanted to get his "name back," and that the actions he was taking were his "last resort."
Dorner began the shooting rampage Sunday when he targeted Monica Quan, 28, and her fiancé, Keith Lawrence, 27, according to investigators. Quan's father is a retired LAPD captain referenced several times in Dorner's document.
Monica Quan and Lawrence were fatally shot Sunday while sitting in their car in a parking structure in Irvine, according to police. Authorities also suspect Dorner in Thursday's shooting death of a Riverside police officer.
Dorner "ambushed" the officer and a trainee at a stop light in Riverside, police said.