Chicago police officer fatally shot on South Side

A plainclothes Chicago police officer who was shot in the head while investigating reports of gunfire on the city's South Side has died.

Chicago Police officer John Mirabelli said Monday afternoon that the slain officer is 27 years old and a 3-year department veteran. He didn't identify the officer, but officials have said he works in the department's 7th District.

Police say the shots were fired from a vehicle shortly after midnight Monday in the city's West Englewood neighborhood. Authorities say the officer was also wounded in the leg.

Chicago police say they are investigating.