The victim was exiting onto the I-476 northbound ramp when three bullets hit the passenger side of his car around 9:45 a.m., according to state police. No injuries were reported.
The driver told troopers he had been involved in an on-road altercation with the suspected shooter shortly before.
Investigators believe the suspect fled west on I-76 in a white Chevrolet Impala with tinted windows and Pennsylvania tags. He is described as a black man between 35 and 40 with a "portly" body type, short hair, and "age spots" on his face.
The investigation is ongoing, troopers added.
Anyone with information is asked to call PSP's Criminal Investigation Unit at 215-452-5280.
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