VANCOUVER -- An avalanche forecaster and search and rescue volunteer says there were 11 people in the vicinity of an avalanche on Cowboy Ridge near Whistler Saturday afternoon, including four people who were downslope from the slide.

Wayne Flann told CTV News Vancouver in a Zoom interview that the size three avalanche was likely remotely triggered, meaning that a skier’s movements nearby - but not directly on top of the slope - sent the snow and ice falling.

"A size three avalanche will basically bury a house, bury a car," Flann said. "It's fairly destructive. It definitely could kill you."

Saturday's avalanche happened around 3:15 p.m., according to Whistler RCMP, who tweeted in the evening that they were asking anyone who was in the area at the time to get in touch with them.

Mounties have not indicated that anyone is missing since putting out their call for assistance, and Flann said no one was hurt in the slide.

"They're very lucky," he said. "I mean, there were two different groups on the slope at the time the avalanche happened, and there were at least 11 people in the area at the time."

Four of the people in the area were downslope from the avalanche, and three of them were partially buried, Flann said.

"They lost all their gear," he said. "It was a big event and they were very lucky to have survived it."

A total of 16 search and rescue personnel responded to the area, where several avalanches have been triggered in recent days.

On his blog, Flann posted photos of a size 2.5 avalanche that was triggered on Thursday in the same area.

"There's been a persistent weak layer this year," he said, describing the snow pack. "There's a crust that's down anywhere from 20 to 40 centimetres to two metres, maybe even deeper in places, and it's been a problem all year."

"When we get these persistent weak layers, you have to be extremely careful about where you go and what you do," Flann said.