Investigators identified one of the suspects as 17-year-old Zayki Davis.
Zayki Davis
The victim, Zahkir Whitfield, was shot while on the bus near 40th Street and Girard Avenue in West Philadelphia on Saturday afternoon. He was a student at Upper Darby High School.
The video shows three of the suspects inside a convenience store.
Then, around 12:45 p.m., they are seen waiting for a SEPTA bus in the area of Girard and Ridge avenues, and then boarding it together.
Just before 1 p.m. the fourth suspect is seen waiting at a stop, and then getting on the same bus.
Philadelphia police say just a few minutes after that six juveniles started fighting in the back of the bus.
When the driver stopped near 40th Street and Girard Avenue one of the suspects got off.
But, as the video shows, he then fired into the bus before running away.
Police say that single gunshot struck Whitfield in the chest, killing him.
If you recognize the suspects, you're asked to call or text police at 215-686-TIPS (8477).
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