Editor's note: This updates with snowboarders down off the mountain, corrects park statement that the two had stayed in a snowcave, and provides additional search details.

Two snowboarders who became stranded by a snowstorm at Mount Rainier National Park on Sunday were found Tuesday morning and managed to walk down off the mountain later in the day.

The two, Derek Tyndall, 21, of Sumner, Washington, and Thomas Dalle, 20, hometown unknown, had spent Sunday snowboarding in the area above Paradise before they became lost in white-out winter snow conditions while descending from Camp Muir, park officials said. When they couldn't continue down the mountain, they managed to find some shelter under a rock overhang, officials said Tuesday.

On late Monday afternoon searchers thought they saw the missing snowboarders in the distance. Because of difficult terrain and low visibility, however, they were not able to make contact with these individuals before nightfall. Park officials said Tuesday it most likely was the two snowboarders.

Tuesday morning a stronger search response was launched over a greater area of the park, with volunteers from Tacoma, Olympic, and Seattle Mountain Rescue Teams, as well as four dog teams from the Washington Search and Rescue Task Force.

Hampering the search effort was deep snow that at times was chest-deep, park officials said.

The two young men were found by one of the search groups in the Upper Stevens Creek drainage. They were then led down the mountain by rangers to Paradise, where they declined further medical attention.