WAYNESBURG — State police say three teens were inhaling compressed air cleaner before they were involved in a collision last fall in southwestern Pennsylvania that killed four people and seriously injured four others.

Police say an autopsy found Difluoroethane in the system of 18-year-old Cullin Frazar, who was driving an SUV, and in 18-year-olds Benjamin Hardy and Bryon Kerr, who were in the car with him. All three died in the crash.