At about 11:30 on Wednesday night a gunman wounded a 16-year-old boy and 29-year-old man.
It happened near the 4100 block of Pennsgrove Avenue in West Philadelphia.
The man was shot repeatedly.
Both victims are in critical condition at a local hospital.
About a half-hour earlier, two men were shot while they walked along the 2500 block of West Somerset Street in North Philadelphia.
Each man suffered gunshot wounds to the legs.
The victims -- in their 30s -- were taken to Temple University Hospital in stable condition.
The suspects ran off and remain on the loose.
Detectives are trying to find motives and suspects for the two double-shootings.