The discovery was made around 3 p.m. on the 1800 block of Diamond Street.
Police say a 35-year-old woman and an adult man were both shot multiple times. Both victims were pronounced dead at the scene.
No arrests have been made and no weapons were recovered.
Further details on the shooting have not been released.
A $20,000 reward is being offered for information leading to an arrest and conviction.
Anyone with information is asked to call police at 215-686-TIPS.