A 13-year-old boy who police say accidentally shot himself and a 12-year-old girl inside a Philadelphia home is facing charges.

Police say the teen was charged Tuesday with aggravated assault, weapons offenses and related charges. Authorities did not identify the boy because he's charged as a juvenile.

Authorities say officers responded to the home Monday night for a report of a person with a gun, and found the girl with a gunshot wound to her right knee. She remains hospitalized in stable condition.

Police say the boy was waving a gun when it went off, striking him in the left hand and hitting the girl. He was taken by a private vehicle to a hospital.

The gun has not been recovered. Authorities are investigating who it belongs to.