The bodies of a Nepalese guide and a German man were recovered and rescue pilots had spotted seven other bodies on the slopes of Mount Manaslu in northern Nepal, the eighth highest mountain in the world at 8,156 metres.
Police in Nepal say many of the climbers were French or German, but the identities of many of the victims were still being confirmed. Spanish officials have confirmed one of the dead was a Spanish citizen.
Ten other climbers survived the avalanche but many were injured and flown to hospitals by rescue helicopters.
The avalanche hit the climbers at a camp at 7,000 metres as they were preparing to head toward the summit. The search and recovery efforts were suspended on Sunday night and resumed at daybreak on Monday.
Montreal cardiologist missing
Isabelle Ouimet said her brother, Dr. Dominique Ouimet from Montreal, is among the people who are unaccounted for in the wake of the disaster.
She said officials from Canada's Foreign Affairs Department told her a search is underway for her brother and the other missing climbers.
"On the mountain there are several teams, and I didn't know their teams had been hit," Ouimet said. "One of their guides is dead. Another climber is in hospital."
She told CBC's French news service that her brother was on his ninth mountaineering expedition. He has already summited Mount McKinley in Alaska and Aconcagua in Argentina, the highest peaks in North and South America, respectively, and was trying to beat his altitude record of 6,960 metres.
He was also using the expedition to raise money for his hospital, the St-Jérôme Regional Hospital north of Montreal.
"He was using it to pursue his two passions at the same time," Ouimet said.
Revelstoke climber survives
At least one other Canadian, Greg Hill from Revelstoke, B.C., survived the avalanche. He was with German climbers who were trying to set a speed record for reaching the summit.
"A huge avalanche swept through Camp 3 at 4:45 a.m. on Manaslu, catching lots of people in their sleeping bags, many dead, and injured," Hill wrote on his Facebook page Sunday.
Camp 3, one of four intermediate camps on the way to the summit, is at an altitude of 6,800 metres.
"Luckily our team is fine, and helped with the rescue ... but my heart goes out to all the others," wrote Hill, who is married with two children.
Back in Hill's home town of Revelstoke, friend Mike Gravelle was glad to hear his friend was alive.
"The fact that he got out is great, being in this industry you deal with that a lot," said Gravelle.
"I lived in Whistler for many years and have lost many friends and it is a risk that we take, it's part of our lives, you know. There's a lot of people that have never made it out, so the fact that he's out and is going to be back in Canada is great news.
'Passion for mountains'
On Wednesday in an interview with Radio-Canada, Dominique Ouimet said the expedition at that point was going "well enough." He was suffering from a bout of pharyngitis — an inflammation of the throat — and had descended to base camp from Camp 2 to recover, but was still going to attempt to reach the summit.
Ouimet also said turning his expedition into a fundraising trip had made it an even better undertaking.
"I've had a passion for mountains for several years. It's something that's fairly individual and that's sometimes incomprehensible, but it's an addictive enough passion. And so I said why not unite my personal passion with something useful, something a little more altruistic that goes beyond just one person? And I have to say it's made it a greater experience."
Asked about the risk of catastrophe, he said the myriad safety rules of mountaineering tend to occupy his thoughts more than the chance of something going horrible wrong. "You're very much in the moment, in every little movement, because you're on a glacier and there are crevasses."
Crowds and global warming dangerous
It is currently the beginning of Nepal's autumn mountaineering season, which comes right after the end of monsoon rains, making weather conditions unpredictable and climbing dangerous.
"There has been a great deal of rainfall, and of course at that kind of altitude it falls as snow," said GRN reporter Tom Bell, who is based in Kathmandu, Nepal.
Fresh loose snow increases the risk of avalanches.
"So many of the climbers have been stuck in camp for the past few days hoping the weather would clear so they could move on up and attack the summit. And that's what they were doing when the avalanche struck," Bell told CBC News.
Many climbers have also warned in recent years that climbing conditions have deteriorated and risks of accidents have increased due to global warming.
Veteran mountain guide Apa, who has climbed Mount Everest a record 21 times, travelled for months across Nepal earlier this year campaigning about the effects of global warming on the mountain peaks.
He told The Associated Press the mountains now have considerably less ice and snow, making it harder for climbers to use ice axes and crampons on their boots to get a grip on the slopes.
231 climbers on the mountain
Bill Amos, of Portland, Oregon, an avid mountaineer and ice climber, who founded the mountaineering apparel company NW Alpine, said "it's super sad when our fellow climbers die."
Amos said his initial thought when he heard about the deadly avalanche in Nepal was that the mountain was being overcrowded with climbers.
There was a total of 231 climbers and guides on the mountain at the time, but not all were at the higher camps, officials said.
"That seems to be the same thing that's going on in Everest," he said. "All of that is overcrowding and these commercial expeditions trying to make money."
Amos added that people who venture into the mountains need to understand the risks and dangers associated with backcountry travel and be able to spot avalanche terrain and dangerous snowpack.
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