As widely reported in the mainstream media, at least twelve Sherpas have been killed on Everest in a huge serac collapse.
One of the most comprehensive reports on this tragedy is by Alan Arnette, and he explains on his website:
"Around 6:30 am, April 18th, an ice avalanche occurred off the West Shoulder of Everest hitting an area just below Camp 1 which is located at 19,500′ but near the top of the Icefall. The estimated altitude was 5800m or 19,038′."
The Sherpas were fixing ropes in preparation for the spring climbing season in a heavily crevassed section of the notorious Khumbu Icefall known as the Popcorn Area (photo on Alan Arnette's Website). A huge serac, which has caused major concern on Everest for some years, collapsed with a large amount of Sherpas working on the lower part of the mountain.
From Alan Arnette's report:
"Immediately after the avalanche spray subsided, Sherpas searched the debris field and found 8 survivors. Eyewitnesses reported boots protruding through the snow. Many however were buried and their bodies recovered later. A person can suffocate within minutes when buried under heavy snow."
It is thought that around 100 Sherpas were above the incident and are now waiting on the mountain until the route is safe for them to descend.
This video shows a similar collapse from 2009 that occurred in a similar place (just slightly lower down) on the mountain.
More information on this tragedy: