If the deaths are confirmed, it would be the deadliest U.S. avalanche since three climbers were killed in a slide in Washington's Cascade Range two years ago.

They were likely killed under the weight of snow nearly as deep as a 10-story building, Alaska State Troopers said Wednesday.

Three skiers who had flown by helicopter to a remote mountain range were swept away by an avalanche and likely killed under the weight of dozens of feet of snow, Alaska State Troopers said Wednesday.

The large avalanche occurred Tuesday afternoon in the Chugach Mountains near Girdwood, according to the Alaska Department of Public Safety.

Alaska State Troopers said three skiers are likely dead after an avalanche buried them in the Chugach Mountains near Girdwood, Alaska, on Tuesday.

Forecast for avalanches remains high in the area of Alaska where three skiers who were flown by helicopter to a remote mountain range were swept away by and likely killed under the weight of dozens of feet of snow.

Three men are feared dead after being hit by a massive avalanche while on a backcountry heli-skiing trip in Alaska, say officials. Officials believe the party is buried in up to 100ft (30m) of snow, but no bodies have yet been recovered after Tuesday afternoon's incident in the Chugach mountains about 40 miles (65km) east of Anchorage.