One father is the only survivor of a fatal crash on U.S. Highway 59, west of George West.

DPS troopers sent these pictures to 3 News of the accident.

Investigators say the mother and three children --ages one to three-- were killed after their SUV slammed into a tree, caught fire and exploded.

What troopers do not know is if the father was ejected or someone pulled him from the vehicle.

The cause of the crash is under investigation.