An avalanche on Mount McKinley swept a Japanese climbing team off a hill as they tried to descend on a rope line, leaving four presumed dead. One climber survived after tumbling 60 feet into a crevasse.

U.S. National Park Service officials said Saturday that five people were traveling as one rope team early Thursday morning as part of a Miyagi Workers Alpine Federation expedition on the Alaska mountain.

Park Service spokeswoman Maureen McLaughlin said Hitoshi Ogi, 69, survived the fall. He was able to climb out.

The other four fell into the avalanche debris and haven't been seen since. The climbers are presumed dead by either snow burial or injuries suffered in falls

Snowfall and wind have impeded a search for the missing climbers.

Ogi spoke to Park Service employees after the event. He said the climbers were descending the mountain together when the avalanche began, McLaughlin said. They sped up, trying to get down the mountain faster, but the rope connecting them broke when the avalanche struck.