SAN DIEGO - A second suspect was behind bars Thursday in connection with the slaying of a 20-year-old man whose badly burned body was found four months ago in the trunk of a torched sedan alongside a remote Jamul-area road.

Devin F. Gaillard, 21, was jailed Wednesday on suspicion of taking part in the slaying of one-time 4S Ranch resident Dillon Davis, sheriff's homicide Lt. Glenn Giannantonio said.

Last Friday, 21-year-old Miles B. Sharp was arrested in the case. At the time, he was in jail in Humboldt County on unrelated charges.

Firefighters found Davis' remains Sept. 20 after extinguishing a predawn car fire in the 16200 block of Skyline Truck Trail. Authorities have withheld his cause of death and have disclosed no suspected motive for the killing.

It was unclear where the victim resided at the time of his death, though he had relatives living on the East Coast, the lieutenant said.