Results of an autopsy were expected today on a Vicksburg man who was killed in a one-vehicle wreck early Sunday morning, officials said.

David Allen Smith, 23, 135 Red Oak Drive, was pronounced dead at about 1:30 a.m. Sunday after the truck he was driving on a gravel road in Jefferson County hit an oak tree and exploded into flames, officials said.

His two passengers, Spencer Pell, 22, 450 Still Drive, Vicksburg, and David Michael Hobkirk, 22, Crystal Springs, were injured. Pell was treated and released from a hospital in Brookhaven, and Hobkirk remained in University Medical Center in Jackson in good condition this morning, spokesmen for the hospitals said.

Jefferson County Coroner Robert Rollins said this morning that Smith’s body had been taken to Jackson for an autopsy and results were expected later today.

Jefferson County Sheriff Peter Walker said this morning that the truck burst into flames after crashing sideways into the tree. He said the cause of the wreck remains under investigation.

Relatives of Hobkirk’s and Pell’s, who are first cousins, said they and Smith had grown up together.

“Those boys were always best friends,” said Spencer Pell’s father, Robert Pell. He said Hobkirk grew up in Vicksburg but moved to Crystal Springs a few years ago.

The men had left Vicksburg Friday and spent Saturday in Jefferson County preparing their deer-hunting property for future outings, family members said. They were believed to be on their way home when the accident occurred, said Smith’s stepfather, Terry McCraine, who lives in Vicksburg with Smith’s mother, Christy Lynn McCraine.

Smith was a contract employee at LeTourneau Technologies at the time of the wreck.

Services for Smith are planned for Thursday at Glenwood Funeral Home in Vicksburg with burial in Port Gibson.