It all happened shortly before midnight Saturday when police on patrol heard numerous gunshots from the 200 block of South Street.
Those officers saw several active shooters firing into a crowd, Inspector D F Pace said during an early Sunday morning news conference.
One of those officers fired at one of the shooters. It's unclear if that suspect was hit, Pace said.
However, that suspect dropped his weapon and fled.
At least two guns were recovered from the scene, and Pace said one of them had an extended magazine.
"Numerous" shell casings were found along the 200 and 300 blocks.
In all, 14 people were hit by gunfire. Of those victims, three people are dead and 11 more are wounded.
The victims who were killed include two men and a woman. All three suffered multiple gunshot wounds to the body.
Their names have not been released.
*Alert* Emergency personnel are responding to a shooting incident in the area of 3rd and South Streets. Several people have been injured. Please avoid the area.— Philadelphia Police (@PhillyPolice) June 5, 2022
"You can imagine there were hundreds of individuals just enjoying South Street, as they do every single weekend, when this shooting broke out," said Pace.
No arrests have been made.
Pace said at least one of the shooters fled southbound on American Street.
Police are looking for surveillance video to help them identify the shooters.