Police were searching for a man accused of soaking a woman in flammable liquid and lighting her on fire on Christmas Day, Pomona police said.
The man, identified by police as Clarence Duwell Dear, 51, was considered "extremely dangerous."
Police were treating it as a homicide investigation.
Dear and the victim, later identified by police as Dawn Hensley, got into an argument that turned into a physical altercation, and may have been a domestic dispute.
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According to police said Dear chased the woman from the home, doused her with gasoline and then lit her on fire. Police said he may have lit her on fire with a cigarette.
Neighbors told police they saw the 41-year-old victim running from the home in the 1500 block of Cordova Street engulfed in flames before collapsing in the street.
Dear took off and has not been seen since 1:45 p.m. There was no description of a vehicle available.
Neighbors said they stayed with the unidentified victim until LA County Fire officials arrived.
She was treated for severe burns and taken to a hospital where she later died.
If anyone has seen Dear or has information on the incident, they are encouraged to call the Pomona Police Department at 909-620-2085.