Six additional people were killed and many were injured in shootings in Tennessee, Virginia, Arizona, and South Carolina.
After pulling out weapons and firing indiscriminately at one other, at least two men turned a crowded Philadelphia street into a scene of dread Saturday night.
Three persons were killed and 12 others were injured by the time the gunshots stopped.
A horrific shooting outside a club in Chattanooga, Tennessee, a few hours later, sent customers fleeing in terror.
Three people were murdered there as well, including one who was hit by a vehicle, and 14 people were injured, the majority of them were shot.
There have been no arrests in his city as of Sunday evening.
As of Sunday evening, no arrests had been made in the city.
Hundreds of people were out the night before in the district's pubs, restaurants, and music venues.
The kids were climbing up the parked cars' roofs, and all of us out enjoying the night were becoming uncomfortable.
Officers on patrol a short distance away responded to the gunshots by firing at one of the gunmen, potentially injuring him, according to the police.