A Minnesota teenager drove his pickup truck into the back of a car in eastern South Dakota and killed the other motorist, authorities said.

The collision occurred on northbound Interstate 29 roughly 4 miles north of Watertown about 7:50 p.m. Wednesday, the Highway Patrol said.

Dalton DeYonge, 18, of Slayton, was identified Sunday as the driver of the pickup. He was not injured.

Charles Slettedahl, 58, Stockholm, S.D., died in the collision, the patrol said.

Authorities have yet to say why DeYonge hit the pickup ahead of him. The car went into a ditch to the right of the interstate and rolled over.

Slettedahl was driving a 1969 Ford Mustang. His online obituary noted that he enjoyed old cars and motorcycles.