American alpinist Jess Roskelley and Austrian climbers David Lama and Hansjörg Auer were missing after they tried to climb the east face of Howse Peak on the Icefields Parkway and "local search and rescue has assumed the worst," outdoor apparel company The North Face said in a statement. The three were reported overdue on Wednesday, one day after the avalanche struck.
"David, Jess, and Hansjörg are valued and loved members of The North Face family and we are doing everything we can to support their families, friends and community during this difficult time," the company said on its website. "We will continue to keep you updated and ask that you keep our athletes and their loved ones in your hearts and thoughts."
Recovery efforts were on hold because of a continued risk of avalanches, officials said.
Parks Canada said safety specialists immediately responded by air and observed signs of multiple avalanches and debris containing climbing equipment.
"Parks Canada extends its sincerest condolences to the families, friends and loved ones of the mountaineers," the agency said in a statement.
Roskelley, a native of Spokane, Wash., climbed Mount Everest in 2003 at age 20. At the time he was the youngest American to climb the world's highest peak. His father, John Roskelley, was himself a world-renowned climber who had many notable ascents in Nepal and Pakistan, mostly in the 1970s. John Roskelley joined his son on the successful Everest expedition in 2003.
John Roskelley had climbed the 10,810-foot Howse Peak, via a different route, in the 1970s and is said to know the area well. On Thursday he was preparing to go to Canada to gather Jess Roskelley's belongings and see if he could get into the area.
"It's in an area above a basin," he said. "There must have been a lot of snow that came down and got them off the face."
The elder Roskelley said: "When you're climbing mountains, danger is not too far away ... It's terrible for my wife and I. But it's even worse for his wife."
The Associated Press contributed to this report.