Three popular professional alpinists went missing and are presumed dead after an avalanche in Canada's Rocky Mountains.

According to various media reports on Thursday, the missing mountaineers are Jess Roskelley, 36, David Lama, 28 and Hansjörg Auer, 35. They were reportedly killed after attempting to climb a challenging route on Howse Peak in Banff National Park.

However, the Canadian authorities did not disclose the identity of the three missing men but said they were one American and two Europeans, apart from describing them as highly experienced professional mountain athletes.

Roskelley was best-known for climbing Mount Qomolangma at the age of 20 in 2003, which made him the youngest person to reach the world's highest mountain peak at that time.

Lama and Auer were also world-renowned mountaineers who had climbed some of the toughest mountain routes around the globe.

In a media statement, Parks Canada said that the party was attempting the east face of Howse Peak. The statement said, "Parks Canada visitor safety specialists immediately responded by air and observed signs of multiple avalanches and debris containing climbing equipment."

Meanwhile, Parks Canada visitor safety specialist Stephen Holeczi said the three men probably started their ascent on Tuesday. They were reported missing on Wednesday.

Without divulging any further details, Holeczi mentioned that there was "strong evidence" that all three climbers were deceased.

However, there is no timeline for when search and recovery efforts can begin as Holeczi stated that it's all because of bad weather and avalanche risk in the area.

(With input from agencies)