The association says Jeeps, pickup trucks and UTVs have been seen on snowmobile trails in the Mirror Lake, Soapstone and Mill Hollow areas over the weekend.
Vehicles over 800 pounds are prohibited and face fines for trail damage and repairs.
The snowmobile association is asking anyone who sees illegal vehicles to report the incidents to the Utah Department of Natural Resources’ Division of Law Enforcement.
Mirror Lake Highway is closed to all vehicle traffic in the winter. It will reopen to cars in the spring once the snow melts.
