MCBRIDE, British Columbia (AP) — A "very large" avalanche in the western Canadian province of British Columbia left five people riding snowmobiles dead Friday, the provincial coroner's service said.

Barb McLintock of the B.C. Coroners Service said the avalanche took place in an area where several groups were snowmobiling. She said two coroners were dispatched from Prince George and the Royal Canadian Mounted Police were investigating.

The McBride RCMP said Friday evening it was coordinating the search for a number of snowmobilers involved in the avalanche in the Renshaw area east of McBride, which is about 210 kilometers (130 miles) southeast of Prince George.

A helicopter was dispatched to the area to assist and two search-and-rescue technicians were on the scene almost immediately because they were already in the area, police said.

Rescue crews quickly learned that at least three separate groups of snowmobilers were caught in the avalanche, and they assisted with the rescue of several people throughout the afternoon and searched for people believed to have been buried, RCMP said.

Karl Klassen of Avalanche Canada said the "very large, significant" avalanche appeared to be human-triggered, but he did not elaborate.

"There are layers of concern in the snowpack in many parts of this region (and others) and a fairly significant weather event added rain and snow to the snowpack over the last few days followed by clearing and cooling today," he said in a statement. "This may have produced stresses in the snowpack capable of producing large avalanches and this condition could take several days to settle and bond."