Avalanches killed three skiers and critically injured four others Saturday in Austria's Alps (search), and authorities suspended a search for a missing American snowboarder.

One avalanche began Saturday afternoon in the popular winter resort of St. Anton, police said. Two people suffocated in the crush of snow and ice, and two others were seriously injured and taken by helicopter to hospitals.

The Austria Press Agency quoted authorities in the western alpine province of Tyrol as saying one of the two skiers who died was a Canadian, and a missing snowboarder was an American. Authorities suspended the search for the missing snowboarder until Sunday morning.

Officials said the injured survivors also were Canadians who were traveling together on a ski holiday.

Later Saturday, another avalanche in the southwestern province of Vorarlberg (search) killed one skier and critically injured two others, Austrian television reported. Their nationalities were not immediately known.

Officials had raised the five-step avalanche (search) alert to level four in recent days after a combination of heavy snowfalls, strong winds and subsequent mild temperatures made snow cover unstable and prone to breaking away.