WEST HOMESTEAD — Authorities say an exchange of gunfire between two men in cars led to a crash that injured an off-duty police officer.

Allegheny County police say a 17-year-old in a car was being pursued by another vehicle in West Homestead at about 7 p.m. Saturday. Witnesses reported hearing at least seven gunshots exchanged.

Police say the teenager’s car sideswiped a truck driven by a 27-year-old police officer who was on his way home. The truck rolled over and hit a utility pole. The car crashed through a fence into a parked tractor-trailer, and someone from the other vehicle fired at the teen.

Both officer and teen were reported in stable condition, the teen with a gunshot wound to the leg. The shooter hasn’t been identified.