DESCANSO (CNS) - A man's death Monday at the scene of a fire that engulfed a recreational vehicle in the eastern San Diego County highlands prompted an investigation by homicide detectives and a sheriff's arson- explosives unit.

The blaze in the 23400 block of Trappers Hollow Road in Descanso erupted for unknown reasons shortly before 3 p.m., gutting the RV and scorching a roughly 20- by 20-foot patch of brush before firefighters could get the flames under control, Cal Fire Capt. Issac Sanchez said.

The victim, whose name was not immediately available, was found unconscious on the ground a short distance from the burning vehicle. Despite lifesaving efforts, he was pronounced dead at the scene.

"The Sheriff's Homicide Detail was called to the scene and has assumed investigative responsibility," according to sheriff's Lt. Rich Williams. "The Sheriff's Bomb/Arson Unit also responded to investigate the cause of the fire."

The medical examiner's office will conduct an autopsy to determine the cause and manner of the man's death and will also work to positively identify him.