The body was discovered at East Covina Hills Road near East Via Verde Street at about 3:45 a.m. Authorities say an L.A. County sheriff's deputy and an LAPD officer were driving along Covina Hills Road when they noticed something burning. They both stopped, and the deputy was able to put out the flames.
Investigators believe the person was killed elsewhere, and then dumped at the location and set on fire.
Because of the condition of the body, officials say it will take some time to identify the victim and determine a cause of death.
"The body is badly burned, so right now, we can't tell if it's a man or a woman, a child or an adult," said Lt. John Corina of the L.A. County Sheriff's Department.
There are hills on both side of the area, and no homes face the location. Detectives are canvassing neighborhoods to find witnesses.
Covina Hills Road is closed between Via Verde Street and Holt Avenue due to the investigation.
Anyone with information is urged to call the L.A. County Sheriff's Department Homicide Bureau at (323) 890-5500.