It happened at 12:30 a.m. Saturday in the 5900 block of Hammond Street in Olney.
Officers arrived to find a number of bullet casings at the scene, but no shooting victims.
They soon learned a 17-year-old boy had been taken to Einstein Medical Center with a gunshot wound to the ankle. He was listed in stable condition.
A short time later, at 2 a.m., a second victim arrived at Einstein. That 16-year-old boy had been shot in the foot. He was also listed in stable condition.
A third victim from the same incident, a 17-year-old boy, arrived at Einstein at 2:45 a.m., also suffering from a gunshot wound to the ankle. He was evaluated, but refused treatment.
A fourth victim, an 18-year-old man was identified to police by family members at 3:30 a.m. He has not been found.
Police tell Action News the suspected gunman, also 18 years old, remains at large.
Anyone with information about the incident is asked to contact Philadelphia Police.
Send a breaking news alert to Action News
Report a correction or typo
Learn more about the 6abc family of apps