Thousands of police officers launched a hunt for one of their own: a former Los Angeles officer angry over his dismissal and wanted over a deadly shooting rampage after warning he would wage "warfare" on those who wronged him.
Authorities issued a statewide "officer safety warning", and police were sent to protect people named in a manifesto that was believed to be written by the sacked policeman, Christopher Dorner, who has military training.
"I will bring unconventional and asymmetrical warfare to those in LAPD uniform whether on or off duty," the manifesto says.
It also asserted: "Unfortunately, I will not be alive to see my name cleared. That's what this is about, my name. A man is nothing without his name."
Dorner has available multiple weapons including an assault rifle, said police chief Charlie Beck, who urged Dorner to surrender. "Nobody else needs to die," he said.
Dorner, who was fired in 2008 for making false statements, was linked to a weekend killing in which one victim was the daughter of a former police captain who had represented him during his disciplinary hearing; the other was her fiance. Authorities believe Dorner also opened fire early yesterday on police in cities east of Los Angeles, killing an officer and wounding another.
Police said Dorner (33) implicated himself in the killings with the multi-page manifesto.
In a Facebook post, Dorner said he knew he would be vilified by the police department and the news media, but that "unfortunately, this is a necessary evil that I do not enjoy but must partake and complete for substantial change to occur within the LAPD and reclaim my name".
Beck detailed Dorner's alleged crimes in a press conference in an underground room at police headquarters, where extra security was deployed.
The chief said that there had been a "night of extreme tragedy in the Los Angeles area" and that all measures were being implemented to ensure safety.
As police searched for him, the Los Angeles area was on edge. The nearly 10,000-member LAPD dispatched officers to protect potential targets.
The department also pulled officers from motorcycle duty, fearing they would make for easy targets.
Los Angeles officers guarding a "target" named in the posting shot and wounded two women in an apparent case of mistaken identity, authorities said.
It's not clear if the target is a person or a location.
Beck said one woman was in stable condition with two gunshot wounds and the other was being released after treatment.
Dorner's LAPD badge and an ID were found near San Diego's airport and were turned in to police early yesterday, San Diego police Sgt Ray Battrick said.
Dorner allegedly tied up an elderly man in San Diego and unsuccessfully tried to steal his boat on Wednesday.
Naval Base Point Loma was also locked down yesterday. Navy spokesman Kevin Dixon said a navy person reported someone matching Dorner's description in the area.
Dorner is wanted over the killings of Monica Quan and her fiance, Keith Lawrence. They were found shot in their car at a parking structure Sunday night, authorities said.
Early yesterday, the first police shooting occurred in Corona and involved two LAPD officers working a security detail. One officer was grazed by bullets.
Later, two officers on routine patrol in neighbouring Riverside were ambushed at a stop light, said Riverside Lt Guy Toussaint. One died and the other was in surgery.