INDIANAPOLIS (AP): Authorities say an Indianapolis firefighter has been placed in a medically induced coma after breathing in smoke while fighting a suspected arson at a vacant house.

Fire Department officials say firefighter Chris McGrone was inside the house early Friday when his mask was knocked from his face.

Capt. Rita Burris says McGrone was first taken to a hospital with what was considered a slight injury, but doctors determined his condition was more serious because of breathing in smoke amid the super-heated environment.

Burris says McGrone could be kept in a coma for several days as doctors monitor his condition.

Investigators blamed arson for the fire that badly damaged the house in a neighborhood northeast of the city's downtown.