Oakland County's top elected official suffered several broken bones and a gash to his scalp when the car he was riding in collided with another vehicle in Auburn Hills, north of Detroit.
A doctor at McLaren Health Center in Pontiac said during a news conference Friday night that county executive L. Brooks Patterson was undergoing surgery.
The Detroit Free Press reports Patterson had two broken wrists and a broken leg.
Police say Patterson's county-issued Chrysler hit a Volkswagen about 4 p.m. at an intersection. The Volkswagen is believed to have turned in front of Patterson's car. The crash is under investigation.
Patterson was being driven by a state police trooper. His driver and two men in the Volkswagen also were injured. None of the injuries are believed to be life-threatening.
