BANFF, Alberta — Three renowned mountain climbers are presumed dead after an avalanche in Alberta's Banff National Park, Canadian officials said Thursday.

Outdoor apparel company The North Face said that American Jess Roskelley and Austrians David Lama and Hansjorg Auer disappeared while attempting to climb the east face of Howse Peak. They were reported overdue on Wednesday.

"They are missing, and local search and rescue has assumed the worst," the firm said in a statement.

(2/3) Based on the assessment of the scene, all three members of the party are presumed to be deceased.We extend our sincerest condolences to the families, friends and loved ones of the mountaineers. — Banff National Park (@BanffNP) April 18, 2019

Roskelley climbed Mount Everest in 2003 at age 20. At the time he was the youngest American to climb the world's highest peak.

Jess Roskelley in 2003. Elaine Thompson / AP file

Recovery efforts were put on hold because of a continued risk of avalanches.

The men were acknowledged for "highly experienced" professional mountain athletes.

Roskelley's father, John Roskelley, was also 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.

Jess Roskelley grew up in Spokane, Washington, where his father was a county commissioner. His father told The Spokesman-Review the route his son and the other climbers were attempting was first done in 2000.

"It's just one of those routes where you have to have the right conditions or it turns into a nightmare. This is one of those trips where it turned into a nightmare," John Roskelley said.

John Roskelley had climbed the 10,810-foot Howse Peak, via a different route in the 1970s and knows 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.

"When you're climbing mountains, danger is not too far away," John Roskelley said. "It's terrible for my wife and I. But it's even worse for his wife."