Kareem El was gunned down on the Schuylkill Expressway early Sunday morning.
Someone pulled up alongside his car just before 3 a.m. and opened fire.
Police and El's family want to know who did it and why.
"I feel angry. A lot of anger," El's cousin, Kenneth Robinson told NBC10's Byron Scott. "I'm baffled that he had to experience that kind of death. . .He doesn't have enemies to my knowledge."
El, who was 29, was killed as he drove eastbound on I-76 between the City Avenue and Montgomery exits.
His younger brother, Derick Lewis-El, got the news a short time later from his mother.
"She was yelling. She said, 'These people out here are telling me Kareem is dead,'" Lewis-El said.
Lewis-El said he last saw his brother a few hours before the shooting. Louis said he doesn't know where Kareem was headed to or coming from when he was murdered.
Pennsylvania State Police are hoping somebody saw something and will call or contact them.
Lewis-El says his family is praying, continually "and we're going to get through it."
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