CHICAGO (CBS) -- A Chicago Police officer was wounded by an accidental gunshot from another officer's firearm in Englewood this week, according to the Civilian Office of Police Accountability.

The incident happened a little after 7:30 p.m. Monday in the 5600 block of South Shields Avenue. Chicago Police initially said officers were conducting a traffic stop, but COPA said the event occurred after a trespassing incident at 357 W. 56th Pl.

COPA said officers were monitoring the area through a POD camera, and saw a group of people in the alley. Officers arrived in four unmarked squad cars, and began talking to the people in the alley – as well as someone driving a black sedan, COPA said.

While on foot, several officers tried to talk to the driver of the black sedan, but the driver left the scene – hitting a squad car on the way, COPA said. Two officers fired their guns at the sedan, COPA said.

Preliminary information indicates an officer who was firing at the sedan accidentally shot a fellow officer in the hand, COPA First Deputy Chief Administrator Ephraim Eddy said in a news release.

The officers involved will be placed on routine administrative duties 30 days.