"It was crowd behavior — some hooligans were creating problems, but things are getting back to normal," said Sushil Ghimire, secretary of Nepal's Tourism Ministry. He and other top officials were to fly by helicopter Thursday to base camp.
While it was unclear just how many of the 400 or so Sherpas on the mountain had joined the walkout, a number of expedition companies have already canceled their climbs, and the lucrative climbing season is in disarray. Most attempts to reach Everest's summit are made in mid-May, when a brief window normally offers better weather.
Without the help of the Sherpas, who are key guides and also haul tons of gear up the mountain, it would be nearly impossible for climbers to scale the mountain. Many climbers will have to forfeit most or all of the money they have spent to go up Everest — at a cost of $75,000 or more.
"It is just impossible for many of us to continue climbing while there are three of our friends buried in the snow," said Dorje Sherpa, an experienced Everest guide from the tiny Himalayan community that has become famous for its high-altitude skills and endurance.
Thirteen bodies were recovered after the avalanche. Three Sherpas were still missing in the ice and snow, and are presumed dead.
"I can't imagine stepping over them," Dorje Sherpa said of the three guides.
American climber Ed Marzec, 67, said by phone from base camp that Sherpas were loading their equipment onto a helicopter.
"There are a lot of Sherpas leaving this morning, and in the next two days there will be a huge number that will follow," said Marzec, 67, who is from California. He said he had already decided to abandon his climb.
But Marzec said some smaller companies were hoping to go ahead with their summit attempts.
Tusli Gurung, a guide who was at base camp Wednesday, estimated that nearly half the Sherpas had left.
Seattle-based Alpine Ascents International announced it was calling off its expedition. "We have all agreed the best thing is to not continue this season's climb, so that all can mourn the loss of family, friends and comrades in this unprecedented tragedy," the company said on its website.
New Zealand-based Adventure Consultants also said it was canceling its expedition.
Friday's avalanche was triggered when a massive piece of glacier sheared away from the mountain along a section of constantly shifting ice and crevasses known as the Khumbu Icefall — a treacherous area where overhanging ice can be the size of office buildings.
The disaster has reignited a debate over the disproportionate risks the Sherpas take on Everest, where most climbers are well-heeled amateurs with little or no experience at high altitudes. That means Sherpas are needed to create miles of lines of fixed ropes, carve steps in the ice and snow and carry nearly all the equipment. At times, they are also "short-roped" directly to weak climbers to help them get up the mountain.
Because of their additional work, many have to pass through the Khumbu Icefall dozens of times, each time exposing themselves to the treacherous conditions there.