Investigation continues, State Police said.
They said Michael Martin, 26, drove his car on U.S.165 south of here into the back of the truck driven by Gregory Sprinkle, 45, of Leesville.
The truck ran off the road, rolled over and hit a tree, killing him and Betty Sprinkle, no age available, and Daylan Sprinkle, 3.
Another passenger in the truck had minor injuries.
Martin, of Alexandria, and his passenger, Freddy Bohler, 33, of Lake Charles, also had minor injuries. Each, police said, claimed the other was driving.
Impairment and speeding are suspected factors in the crash.
The investigation is continuing, and charges are pending.