It happened in the 4900 block of Broad Street just after 9:30 p.m. Wednesday.
Investigators say the gunman walked up to the 37-year-old victim and shot him once in the chest.
That victim has been identified as Frank Pralour from 200 block of E. Providence Road in Lansdowne, Delaware County.
Pralour was found lying on the street and holding a gun, police say.
He was later pronounced dead at the hospital.
Police say they have a description of the killer and are now on the hunt to make an arrest.
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