An off-duty Chicago police officer has shot and wounded a man who authorities say struck the officer with a baseball bat.

The Police Department said in a news release that a 37-year-old officer was walking about 10:30 p.m. Saturday in a West Side neighborhood when he saw an "aggressive male subject" holding his waistband. The release says the officer began a patdown, and the person "called out to family members."

A 32-year-old man came out of a house with a bat and hit the officer "multiple times in the upper body" before the officer fired at him. The man underwent surgery at a hospital.

The officer had injuries that were not life-threatening and has been placed on routine administrative duty for 30 days.

The Independent Police Review Authority is investigating.