Gunshots were reported just after 5:00 a.m. at the intersection of Tioga Street and Kensington Avenue.
According to Lt. Ray Evers, an altercation broke out inside a car between a civilian and an off-duty police lieutenant.
The altercation led in to an assault with the officer discharging his gun once, Evers said.
There were no reported injuries.
The incident remains under investigation.