FRACKVILLE, Pa. (AP) - State police say a trooper was severely injured when he was struck by his own patrol car while helping a motorist on Interstate 81 in eastern Pennsylvania.Police say Sgt. Robert Bemis pulled over to the side of I-81 in Schuylkill County on Friday to help a man whose car had caught fire. They were standing near mile marker 121 when a passing motorist lost control of her SUV, which struck the unmarked patrol car, which hit Bemis and the man.Bemis, a 22-year state police veteran, was flown to Geisinger Medical Center in Danville with serious injuries. He is assigned to the Bureau of Training and Education in Hershey.The other man was taken to the hospital with minor injuries. The passing motorist and her two passengers were taken to a hospital for precautionary treatment.No charges have been filed. The interstate was closed for about five hours.