The suspects, who are also teenagers, were captured by surveillance cameras at the Broad and Allegheny Avenue subway stop.
Police say, just a few blocks away on North 17th Street, they approached the 15-year-old victim.
One of them grabbed his own waistband as if he had a gun, police say, and demanded the victim's cash.
The victim gave them his money and the suspects ran off.
If you recognize the suspects you are urged to call police at 215-686-TIPS (8477).
