MONTREAL, April 23 -- Three world-renowned professional mountaineers killed by an avalanche in the Canadian Rocky Mountains had reached the summit of difficult Howse Peak and lost their lives on the descent, Parks Canada said on Monday.

The mountaineers, Jess Roskelley, 36, of the United States, and Austrians Hansjorg Auer, 35, and David Lama, 28, disappeared last week on a climbing expedition at the east face of Howse Peak, a particularly tough summit in Albertas Banff National Park.

The federal agency, Parks Canada, announced Sunday that their bodies had been found.

"While details are limited, the Roskelley family confirmed that the three climbers were successful at summiting Howse Peak," Parks Canada said in a statement read during...