An accident involving a moped seriously injured a rural Clintonville man Tuesday evening. According to the Waupaca County Sheriff’s Office, the 64 year old man was driving the moped west on Knaack Road in the Town of Larrabee just after 8:30 when the moped left the roadway and struck a mailbox post. The man was found by a passerby lying in the roadway. He was flown by ThedaStar Helicopter to ThedaCare Regional Medical Center in Neenah with serious injuries. The man’s name has not been released, and the cause of the crash remains under investigation.