By Keith Coffman
DENVER, March 3 (Reuters) - A backcountry skier was killed and another critically injured in a weekend avalanche they apparently triggered on a northern Colorado mountain pass, a day after three other people died in snowslides across the country, authorities said on Sunday.
The two men in Colorado were cross-country skiing Saturday on the western side of Cameron Pass, about 135 miles (217 km)northwest of Denver, when they were buried in the avalanche, said Kent Minor, manager of State Forest State Park.
"There were two sets of ski tracks going in, so the assumption is they caused the avalanche," Minor said, adding that the slab of snow and ice that broke loose was a quarter-mile (0.4 km) wide and 300 to 400 yards (270 to 370 metres) long.
The two skiers were outfitted with avalanche-locator beacons, and rescuers on snowmobiles reached them late Saturday afternoon after battling through deep snow and steep, rugged terrain, he said.
The first skier they reached was found dead, and rescuers then dug out the second man, who had been buried for 90 minutes, Minor said. Neither victim has been identified.
Minor said it took rescuers on snowmobiles, snowshoes and snow sleds more than five hours to get the injured man to a spot where a helicopter could land and airlift him to the hospital, where he was listed in critical but stable condition.
Crews returned to the area on Sunday morning to retrieve the body of the dead skier, Minor said. A dog that accompanied the pair has not been located, he said.
Scott Toepfer, a forecaster with the Colorado Avalanche Information Center, said Saturday's incident was the fourth avalanche-related death in Colorado this season and the 13th nationwide.
Toepfer said the Colorado fatality brought to four the number of U.S. avalanche deaths so far in March, including a snowmobiler in Utah, a skier in Wyoming and a climber in New Hampshire who were all killed in separate snowslides on Friday.
In a typical year, 25 people in the United States perish in avalanches, he said. (Editing by Steve Gorman and Eric Beech)