DETROIT (AP) — Michigan State Police have warned of a man who was allegedly impersonating police and making traffic stops over the weekend.

Authorities said they received reports of a man in an unmarked car identifying himself as a state trooper who made stops around 7:30 p.m. Saturday near Interstate 96 and Davison Avenue in Detroit.

The man was reportedly wearing a black uniform and driving a black Dodge Charger with red and blue lights.

Police said troopers don’t use unmarked cars for traffic stops.

State police advised anyone uncertain of being stopped by an unmarked car to slow down, use hazard lights, drive to a public place and call 911.