Police are looking for a suspect who opened fire on a crowded bus Saturday night, wounding four people including three teenagers.

It was a traumatizing ride for dozens of people on board SEPTA's Route 15 bus when police say a man pulled a gun from his bag and started shooting at passengers.

Police continued their search Sunday for a gunman who shot and wounded three children and a woman on a SEPTA bus after an altercation Saturday evening. The Route 15 bus was at 33rd Street and Girard Avenue in Fairmount Park when a man fired a gun inside the bus,