Three Sherpa climbers missing on Mount Everest after snowfall.

Three Sherpa climbers are missing after falling into a deep crevasse on a treacherous section of Mount Everest just above the base camp. The area is the Khumbu Icefall, a constantly shifting glacier with deep crevasses and huge overhanging ice that can be as big as 10-story buildings. A rescue helicopter was trying to locate them while rescuers searched on foot.