The Wyoming Highway Patrol says alcohol may be to blame in a motorcycle crash that claimed the life of a Great Falls, Montana man Sunday evening.

Sergeant David Wagener says 51-year-old Thomas French was headed east on U.S. Highway 30 about 12 miles west of Medicine Bow, when he lost control of his motorcycle.

French, who was not wearing a helmet, was thrown from the bike and died at the scene.

The crash marked the 21st motorcycle fatality in Wyoming this year.