A manhunt is underway for a former Los Angeles Police Department officer believed to be targeting officers and their families.
Christopher Dorner is wanted in connection with the ambush-style slaying Thursday morning of a Riverside officer and another shooting involving LAPD officers, according to police.
Three officers were shot -- two in Riverside, one in Corona. All of the shootings are likely connected to Dorner, a fired cop wanted in connection with a double slaying last weekend in Irvine. The homicide involved a former LAPD officer's daughter and her fiancé.
During a Thursday conference, LAPD Chief Charlie Beck characterized the rampage as a "vendetta against all of Southern California law enforcement." He said Dorner was believed to have multiple weapons including an assault rifle.
Timeline: Ex-LAPD Officer Murder Manhunt | Map: Manhunt Locations| Irvine PD: Christopher Dorner Alert
Dorner was identified as a suspect Wednesday in the slayings of Monica Quan, 28, and her fiancé, Keith Lawrence, 27, who were fatally shot Sunday while sitting in their car on the top level of a parking structure, according to Irvine police. The couple left a Super Bowl party at about 7 p.m. and were found slumped over in their car about 9 p.m.
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Quan's father was the first Asian-American to become an LAPD captain, and also worked on the Asian Gang Task Force. He is now retired. In Dorner's online manifesto, he repeatedly refers to a Randy Quan as being involved in his 2008 firing.
"The attacks will stop when the department states the truth about my innocence," Dorner states in the manifesto. Every officer mentioned in the document was provided with police protection, said LAPD Sgt. Rudy Lopez.
On Thursday at about 1:25 a.m., two LAPD officers were part of a security detail assigned to one of the families when they encountered Dorner in Riverside, Lopez said. The LAPD officers were flagged down by someone who recognized Dorner's vehicle at Magnolia Avenue near the 15 Freeway.
The gunman exited the vehicle and opened fire on officers with a "shoulder-type" weapon, said Lopez. One of the officers was shot, suffering what was described as a "minor" graze wound.
"It's extremely intense," Lopez said. "We're trying to identify where he's been, where he's going. In this case, we are the targets. He's brazen. He's on a hunt to do whatever havoc he can.
"In my 22 years, it’s unusual that this many officers have been targeted."
About 20 minutes later, two Riverside officers responded to Magnolia and Arlington avenues after receiving a call for assistance. Both Riverside officers were shot and transported to a hospital, where one was pronounced dead.
The second officer remained in surgery late Thursday morning, but authorities said the officer is in stable condition.
"By all accounts, it appears they were stopped at a red light and just ambushed by the suspect," said Riverside Lt. Guy Toussaint. "The suspect did flee the scene, and we're in the process of trying to identify and apprehend the suspect at this time."
The LAPD confirmed officers are looking for Dorner in connection with both shootings. Officers said it's a "safe bet" he is armed with a semi-automatic rifle.
Meanwhile, police on protection detail guarding another person listed on Dorner's manifesto shot and wounded two people in a vehicle in Torrance that matched the description of Dorner's vehicle.
The individuals suffered minor injuries and were being treated for their wounds.
“Tragically, we believe it may be a case of mistaken identity on the part of the officers,” Beck said during a press conference on Thursday morning.
Dorner's vehicle was described as a gray Nissan Titan with California license plate 8D83987. That information was displayed on freeway signs Thursday morning in Southern California.
Authorities said it's possible Dorner switched plates to California license number 7X09131.
He also is believed to be connected to an attempted boat theft in the San Diego area. San Diego police were called to the Southwestern Yacht Club located at 2702 Qualtrough Street for an apparent boatjacking around 10:26 p.m. Wednesday.
The 81-year-old boat owner was on his 42-foot sundeck cruiser when a “heavy set man in his 30s dressed in black clothing” robbed him, tied him up and pulled the boat out of the slip officials said. The man could not start the boat so he took some items from the vessel and left according to police.
Authorities asked for the public's help in finding Dorner, whose last known address is 4931 Sharon Dr. in La Palma. Dorner is described as 6 feet tall, about 270 pounds with black hair and brown eyes.
Also early Thursday, the San Diego Harbor Police Department confirmed a badge with Dorner's picture identification was found at about 2:27 a.m. in the center divider on Harbor Drive, near San Diego International Airport.
"Multi-Page Manifesto" Implicated Ex-LAPD Officer
Irvine Police Chief David Maggard said Wednesday evening that Dorner implicated himself in a "multi-page manifesto" that was published online but has since been taken down. A source inside LAPD gave NBC4 the manifesto, which is about 11,300 words long and appears to lay out a plan for targeting those involved in his firing.
In the manifesto -- addressed to "America" and titled "Last Resort" -- Dorner writes that the "horrendous murders" are "a necessary evil."
"I know I will be villified (sic) by the LAPD and the media," he writes. "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."
Dorner goes on to say, "There will be an element of surprise where you work, live, eat, and sleep."