Five snowboarders were killed after apparently triggering a backcountry avalanche in Colorado, authorities said.

Search and rescue crews recovered the bodies several hours after Saturday's slide, which was 600 feet (180 meters) wide, said Clear Creek County Sheriff Don Krueger.

A sixth snowboarder caught in the avalanche was able to dig himself out and call for help, Krueger said. That person's condition wasn't immediately known.

The victims all had avalanche beacons, Krueger added.

The victims' identities weren't immediately known.

Krueger said authorities were "pretty sure" the snowboarders triggered the avalanche.

The avalanche occurred on a busy winter weekend as many skiers and snowboarders took advantage of late season snowfall in the Rocky Mountains.

The area also is popular among photographers and tourists seeking some of the most expansive views in Colorado.

Colorado Avalanche Information Center forecaster Spencer Logan said there have been weak layers in the snowpack since early January.

"Our last series of storms made them more active again," he said.

U.S. avalanche deaths climbed steeply after 1990, averaging 24 a year, as new gear became available for backcountry travel. Until then, avalanches rarely claimed more than a handful of lives each season in records going back to 1950.