VANCOUVER -- A skier is dead and two others are injured after getting caught up in backcountry avalanches Friday afternoon.

Authorities initially said an avalanche struck around 3:20 p.m. in the Poop Chutes area, sweeping up at least four skiers, one of whom was not hurt.

Mounties later clarified that there were actually two avalanches. The one in the Poop Chutes area involved three skiers, while the other was on Spierhead Glacier and seriously injured one person.

Members of the Whistler RCMP detachment, Whistler Blackcomb ski patrol and Blackcomb Helicopters were dispatched to the area with avalanche technicians and search dogs to check for other victims.

Anyone who knows of a skier or snowboarder who was nearby and is "overdue" should contact Whistler RCMP, authorities said.

The Poop Chutes avalanche was classified as Size 3, meaning it could "bury a car, destroy a small building, or break a few trees," according to a definition on the Avalanche Canada website. A Size 2 avalanche, which is much smaller in scale, is said to be capable of burying, injuring or killing people.

Friday's avalanches marked the third incident RCMP officers were called to in the Sea to Sky region in 24 hours – which authorities dubbed a "tragic and tough start" to the Family Day long weekend.

"We have said this multiple times already this year, the snowpack in the backcountry of the Sea to Sky is unstable and is subject to considerable and high avalanche risks," Sgt. Sascha Banks said in a statement.

Banks urged anyone heading into popular backcountry areas to check Avalanche Canada for reports and consider that it might not be "time to be touring in the Sea to Sky."

Banks also stressed the need for appropriate avalanche equipment, training, up-to-date transceivers, and an understanding of the current risks.

One of the earlier incidents was another avalanche that struck Thursday morning near Garibaldi Provincial Park, in the Super Couloir area of Mamquam Mountain. Two backcountry skiers had to be extracted from the area, one of whom was injured.

Squamish RCMP were also called around 11:30 p.m. Thursday after a backcountry skier failed to return from a solo trip in the Elfin Lakes area. Authorities found the man's car left in the parking lot.

An extensive search effort was launched in terrain police called "tough and hazardous," but the man eventually managed to walk himself back to his vehicle late Friday afternoon.

The man suffered extensive exposure injuries, such as frostbite and hypothermia. Squamish Search and Rescue told CTV News he's lucky to be alive.