ASPEN, Colo. — Federal forest officials want visitors of a Colorado hot springs to be very careful about what's lurking inside a remote cabin nearby: Frozen cows.

Rangers believe the cows wandered into the cabin near the popular Conundrum Hot Springs during a snowstorm but couldn't find their way out. Air Force Academy cadets found their frozen carcasses while snowshoeing in late March.

U.S. Forest Service spokesman Bill Kight said Tuesday that water samples have been taken to determine if the hot springs was contaminated by the dead animals.

Rangers want the carcasses gone before they thaw. Removal options include explosives or burning down the cabin.

In the meantime, officials have posted warning signs about the cows around the hot springs near Aspen in the Colorado Rocky Mountains.