WHISTLER, B.C. — The high risk of avalanches is proving deadly after one man was killed and another seriously injured, after going in a permanently closed area in Whistler.

RCMP say they believe the men triggered an avalanche by going in the remote area near West Bowl on skis and snowboards and were swept over a cliff. The area was marked as permanently closed and has been so for 20 years.

"It's an area that's signed as permanently closed, it says `passes will be revoked beyond this point','' said Staff Sgt. Steve Leclair. "It's an area within ski area boundary where people are not suppose to go.''

Leclair said the man on the snowboard was treated at the scene and airlifted to a Whistler clinic before being sent to hospital in Vancouver.

He suffered serious but non-life threatening injuries.

The other man, who was on skis, died of injuries police believe he sustained in the avalanche.

Names have not been released. Leclair said both men worked in Whistler.

He urged that people respect the out of bound signs as they're marked that for a reason.

"They can trigger avalanches that can put persons in the regular ski areas at risk, and ski patrol and the people who come to rescue them'' said Leclair.

Two men were killed after triggering an avalanche on Christmas Eve in British Columbia's interior. Travis Dillman and Derek Henderson were snowmobiling at a lake near 108 Mile Ranch with two others when a small avalanche hit.

They were digging themselves out when a larger one hit. Henderson was found dead by rescue crews that night, while Dillman's body was discovered the next day by a dog team.