KNOX COUNTY, Ind – Indiana Conservation Officers are investigating an off-road vehicle (ORV) accident that happened Sunday and resulted in the death of a Knox County man.

First responders were called to the accident just before noon.

Officers say that 56-year-old William Keith Webb, of Vincennes, was killed when his off-road vehicle went off of a gravel drive, overturned and pinned him beneath the vehicle.

An autopsy will be scheduled early this week.

The investigation is still ongoing.

Conservation officers say that helmets and protective riding gear were not being worn at the time of the accident.