Richfield authorities are investigating the death of a man who was found Wednesday next to a wood chipper.

The man was trimming trees near the intersection of 70th Street and James Avenue S. when a piece of metal flew off a wood shredder and struck him in the back of the head, according to a Fox 9 news report that quoted witnesses at the scene. The station said family members identified the man as Bill Pipes, 51.

Besides police, the Hennepin County Medical Examiner, the Hennepin County Sheriff’s Crime Lab and the Occupational Safety and Health Administration are investigating the death, according to a written police statement.