It happened around 4 p.m. Wednesday near 9th and Jefferson streets at the Dendy Recreation Center.
Police say a 15-year-old male was sitting on a bench when he was shot in the back by a masked gunman.
He was taken to St. Christopher's Hospital for Children where he was placed in stable condition.
On Friday, police said an arrest warrant was issued for 20-year-old Djean Williams.
He is facing charges of Attempted Murder, VUFA, and related charges.
Anyone with information on the case is asked to call police at 215-686-TIPS.
Since 2019, there have been more than 300 shootings at city rec centers.
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