Philadelphia - A traffic stop on a downtown Philadelphia highway turned violent Tuesday when a suspect got back into his car and fled, rear-ended a school bus and then shot and wounded a trooper, state police said.

Three suspects were taken into custody and the trooper has been hospitalized in stable condition, Philadelphia Police Department spokeswoman Leeloni Palmiero said. He was shot in the shoulder.

District Attorney Seth Williams said the confrontation apparently started with a vehicle stop, and that the trooper appeared to have been hit while still in his cruiser. He said the trooper returned fire after being shot and some good Samaritans were involved in the capture of the suspects.

The ordeal began at about 9:30 a.m., along Interstate 676, which runs through the center of Philadelphia, said state police spokeswoman Maria Finn. Two troopers pulled over a vehicle, after which a suspect got back into his car and fled, she said.... Read More: VIN