A 16-year-old girl died in a rollover east of Box Elder in Pennington County Saturday afternoon.

The South Dakota Highway Patrol says the car was going at a high rate of speed when the driver lost control. The car went into a ditch and rolled. The passenger was thrown from the car and died.

A 16-year-old girl who was driving the car was taken to the Rapid City hospital with serious injuries.

Troopers say the girls were not wearing seat belts and that alcohol was not a factor in the crash.