PHILADELPHIA (CBS) – A shooting at a graduation party in Southwest Philadelphia left one person dead and five others injured. Police say about 60 people were attending the party at a park at 70th and Reed Bird Place when police say at least one person came up with a rifle and fired eight or nine rounds into the crowd, shortly after 10 p.m. Sunday.

In all, six people were shot. A 24-year-old man who was shot in the back died at the hospital. He has been identified as Isiaka Meite.

Three boys ranging in age from 15 to 17 and a 16-year-old girl were all shot in the legs and were listed in stable condition. A 21-year-old man was shot in his elbow and was also stable.

Philadelphia Police Commissioner Richard Ross says three men were spotted in the park parking lot when one of them walked up to the celebration and began firing into the crowd.

“It appears as if three males were seen near that parking lot area, around the time of the shooting,” Ross said. “One of whom started shooting into the crowd, indiscriminately and subsequently struck obviously six people, one of whom died. It’s just another case of wanton and senseless violence that we can’t get our brains around.”

Police are working on the descriptions of the men and a possible getaway car.

JUST IN: @PPDCommish says 3 men were spotted in the park parking lot when one of them walked up to the celebration & began firing into the crowd. Police working on descriptions of men and possible getaway car. https://t.co/6lCBRVqtT2 — Trang Do (@TrangDoCBS3) June 17, 2019

Commissioner Ross said at the scene Sunday night that there was no indication of any conflict before the shooting.

“That is deeply disturbing to us, that someone would resort to that, irrespective of what it was about, that you would pull out a gun and fire at people like that without any regard for life whatsoever,” he said.

The park shooting contributed to an extremely bloody weekend in Philadelphia, with nearly 30 people shot before sunrise Monday.

Commissioner Ross responded to a question of what can be done to stem the tide of rampant gun violence.

“We are ramping up our patrols across the city, but it’s also one that should be asked of a lot of other people as well. If you only continue to ask us, we’re never going to solve this issue,” he said.

Anyone with information or surveillance video of the incident is asked to contact Philadelphia Police at (215) 686-TIPS (8477).