Authorities say a 43-year-old  northern Iowa man drowned Monday while trying to remove debris around the Fertile Dam on the Winnebago River.

The Worth County Sheriff’s Department has identified the man as James Thompson, of Fertile. A witness at the scene says the man was one of two people helping to clean up logs and sticks from the top of the dam when a three-pronged hook on a line got caught on a log and pulled the man in.

His body was located about a half-mile down the river shortly after 1 o’clock. Emergency personnel performed CPR on the man at the scene but could not revive him.

An autopsy is scheduled for today to determine the exact cause of death.

By Bob Fisher, KRIB, Mason City