LOS ANGELES (REUTERS) - Authorities will comb through a burned-out cabin in the mountains above Los Angeles on Wednesday for the charred remains of a suspect thought to be an ex-cop who led them on a six-day manhunt climaxing in a shootout there.

Police say even if they find a body in the smoldering rubble, it may take some time to determine if it belongs to Christopher Dorner, the 33-year-old former Los Angeles police officer accused of carrying out a killing spree.

San Bernardino County Sheriff's spokeswoman Cindy Bachman told reporters on Tuesday night that the man who barricaded himself inside the cabin and exchanged gunfire with officers was thought to be Dorner and that "we believe he was still inside"when it went up in flames.

A sheriff's deputy was killed in the shootout in the snow-covered, wooded hills of the San Bernardino National Forest, northeast of Los Angeles, bringing to four the number of killings Dorner is suspected of committing. A second sheriff's deputy was wounded in Tuesday's gunfight.

An angry manifesto posted last week on Dorner's Facebook page claimed he had been wrongly terminated from the LAPD in 2008. He vowed to seek revenge by unleashing "unconventional and asymmetrical warfare" on officers and their families.

Tuesday's climax to the saga unfolded after police learned that a gunman they believed was him had broken into a home near the ski resort community of Big Bear Lake, tied up a couple and stolen their vehicle.

State game wardens later spotted the vehicle and gave chase.

The suspect crashed the car, then commandeered a pickup truck at gunpoint from another motorist, said Lieutenant Patrick Foy of the state Fish and Wildlife Department.

As game wardens pursued him, the suspect fired at them from the window of the truck, and one of the game officers stopped his truck and fired back with a high-powered rifle, Foy said, adding that he did not know whether the man was hit.

Officers got close enough at one point during the chase to recognise the driver as Dorner, Foy said. He ultimately abandoned the pickup and fled on foot into the woods to a cabin believed to be vacant, where he holed up inside and exchanged fire with sheriff's deputies.