Search teams are looking for a snowmobiler missing in the area around Groundhog Reservoir in southwestern Colorado.
The Cortez Journal reports 37-year-old Ronald Wallace was last heard from on Sunday when he telephoned a friend while taking a break on a snowmobiling trip.
A helicopter, a dive team and searchers on foot have been combing the area in eastern Dolores County.
Officials said they were investigating whether Wallace's snowmobile had fallen through thin ice on the reservoir.
The Dolores County Sheriff's Department says Wallace was in excellent health and was trained in survival techniques.