The incident happened just after 9 p.m. at Rising Sun Avenue and Loudon Street in the city's Feltonville section.
According to the District Attorney's Office, 39-year-old Felicia Haynes was involved in a verbal and physical altercation with her former girlfriend, a 35-year-old, and several others outside a bar.
Haynes allegedly entered the bar alone and went to the bathroom, where another physical altercation took place.
Police believe Haynes fired one shot, striking her former girlfriend in the arm and hip.
The victim was taken to the hospital for treatment, and police later tracked down Haynes at her home, where she was taken into custody.
The D.A.'s office said a legally purchased Glock 19 9mm handgun was recovered from Haynes' home. She was licensed to carry, authorities said.
Haynes has been charged with aggravated assault, possession of an instrument of crime, simple assault, and reckless endangerment of another person.
Anyone with information about the shooting should call the police at 215-686-TIPS.
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