One person is dead and eight others were injured in a Fourth of July mass shooting during what officials are calling a “pop-up event” in Southwest Philadelphia on Thursday night.

Police say nine people, three juveniles and six adults, were shot near the intersection of 60th Street and Kingsessing Ave. at 11:40 p.m.

Officers on routine patrol say they found one victim lying on the ground.

Additional victims were discovered by responding officers, and some other victims arrived at area hospitals.

Action News has been told the juveniles are between 14 and 16 years old.

The victim killed has not yet been identified, but police said he is approximately 20 years old. He was shot once in the head and pronounced dead at the hospital.

The other victims are said to be in stable condition.

Officials said the crime scene spans over two blocks and that there may have been a barbecue going on at the time.