The victim was in a residence on the 2600 block of South 65th Street when she was struck once in the left arm just before 1 a.m. on Feb. 7, the department said. She was rushed to the Children's Hospital of Philadelphia where she was placed in stable condition, they added.
No arrests have been made and no weapon was recovered from the scene, according to authorities.
Chief Inspector Scott Small told 6abc that the victim was standing by a window when she was struck by gunfire that came from outside.
The investigation is ongoing, the department said.
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