An unidentified driver was seriously injured about 7:30 a.m. today, when the car he was operating smashed into a tractor trailer on the Mansion House Hill in Mahoning Township. Both vehicles were traveling up the hill from Jim Thorpe when, for some unexplained reason, the driver of the car crashed into the rear of the moving truck. The driver of the car was entrapped for a brief period of time before being freed by emergency workers. He was taken to a nearby hospital. The car was extensively damaged. Minimal damage occurred to the truck. No further details of the crash were available at press time. Mahoning Township police are investigating.