RCMP say they have looked for abandoned vehicles and canvassed area hotels and there is no one that they know of left unaccounted for following a deadly B.C. avalanche.

RCMP direct traffic at the staging area for avalanche search-and-rescue operations near Revelstoke on Saturday. (David Rooney/Revelstoke Current/Canadian Press)

Cpl. Dan Moskaluk said late Sunday afternoon that police were far more optimistic than they had been that Saturday's avalanche on Boulder Mountain did not result in the mass fatalities feared in the first hours after the tragedy.

He said those people that police know were at the event have been accounted for and there have been no new reports of people missing.

A wall of snow engulfed a group of about 200 snowmobilers gathered for the annual Big Iron Shootout, near Revelstoke, B.C.

Police said Sunday that two men, Shay Snortland and Kurtis Reynolds, were killed in the slide, revising a report that three had been confirmed dead.

There were fears the death toll could be in the dozens, but Moskaluk said most of those participating in the event appear to have made it safely off the mountain.

Witnesses said the avalanche appeared to have been triggered after three snowmobilers began high-marking — the practice of snowmobilers racing up the side of the mountain to see who can go the highest.

Police said they were trying to speak with the event's organizers, but it was not clear whether charges were being considered.

Thirty-one people were injured in the slide, including one critically. Moskaluk said 19 of the injured had been released from hospital.

Four patients in more serious condition were transferred to hospitals in Calgary, Kamloops Kelowna and Vernon.

Ben Bassaraba of Fernie, B.C., who was recovering in a hospital in nearby Kamloops, said he was eating lunch with a friend when he heard a loud sound like thunder and looked up to see snow barreling toward them.

"Everybody I could see went under. It was so massive, there was nowhere you could go," Bassaraba said. "I should have been way down deep, I don't know how I ended up on top. I was lucky, but there's people less lucky, that's for sure."

Dozens in search team

The aerial search of the avalanche zone continued for much of the day Sunday. The ground search involving 40 to 50 people with four search-and-rescue teams resumed just after 10 a.m., once the area was deemed safe.

Kathy Berlingette, owner of Smokey Bear Campground Resort in the area, said the event was in a remote place and everyone involved had to use snowmobiles to get there.

She said the avalanche struck in an area known as Turbo Bowl. Officials estimate the snowslide was seven to nine metres deep and 150 metres wide.

Hundreds of people from B.C., Alberta and Washington state were watching the snowmobiling event when the avalanche hit around 3:30 p.m. local time.

The mountain was shut down as search-and-rescue helicopters and avalanche dogs worked to recover the injured.

Rescuers were still scouring the mountain after darkness fell Saturday night. The search was then called off until daybreak Sunday.

Some of the injuries were caused by the force of cascading snow or from snowmobiles colliding, survivors told CBC News.

One man said the snowmobile he was riding was carried about 30 metres down the hill. When he finally came to a stop, he had slammed into another snowmobile.

He described the helplessness survivors felt that some people didn't make it out alive.

"I was at Tim Hortons for breakfast [Saturday] morning and talked to four guys, including one who didn't survive," he said. "We couldn't help him out."

Avalanche risk was high

The Canadian Avalanche Centre had a warning out for the area on the weekend that the risk of avalanche was "considerable."

Officials say the avalanche is one of the largest they have ever seen.

Adam Burke, a member of the Revelstoke Snowmobile Club, said he didn't take part in the Big Iron Shootout because the avalanche potential was too great.

According to the avalanche centre, there have been 10 avalanches in the area since Friday, when the CAC issued an extreme warning for the area. It advised people to stay away from any defined avalanche terrain and steep slopes.

On Feb. 15, an Alberta man was killed in an avalanche while snowmobiling on Eagle Mountain near Revelstoke. Another Alberta man died in an avalanche while skiing near Rossland, B.C., in early January.

Revelstoke is about 300 kilometres west of Calgary and about 400 kilometres northeast of Vancouver.

Risk underestimated

In the winter of 2008-09, 24 avalanche-related deaths were recorded on B.C. mountains, making it the worst season on record.

Five of those deaths involved skiers and snowboarders. A total of 19 snowmobilers died in 11 separate avalanches. One incident, in Sparwood, B.C., claimed eight lives alone.

In February, a British Columbia Coroners Service review panel — put together to study the high number of avalanche fatalities — released its findings.

The panel found that in many of those deaths the individuals involved underestimated the risk of avalanches.

The panel made 15 recommendations, including greater awareness in the snowmobiling community and increasing the coverage and frequency of avalanche forecasts.

With files from The Canadian Press