REVELSTOKE, B.C. (BNO NEWS) — At least three people were killed and more than a dozen were injured in an avalanche on Boulder Mountain near Revelstoke, B.C. during a snowmobile competition, authorities said on Saturday.

The slide happened around 3.30 p.m. local time near Revelstoke, approximately 300 kilometers west of Calgary and about 400 kilometers northeast of Vancouver. There were conflicting reports on the number of casualties.

Dan Moskaluk, a spokesman for the Royal Canadian Mounted Police (RCMP), confirmed that at least three people had been killed, while at least 12 others had been injured. “A large scale rescue operation commenced and is continuing,” Moskaluk said. “We continue to have a tremendous number of emergency rescue assets deployed to assist with this tragic incident. Emergency rescue efforts are continuing.”

The incident happened in the Turbo Bowl area on Boulder Mountain, where an annual snowmobiling event known as “The Big Iron Shoot out” was being held. About 200 people were in the area when the avalanche happened, and some of them may still be missing.

Four Provincial Search and Rescue Teams have been deployed to the area. RCMP Police Service Avalanche trained canine units and other provincial emergency assets are also assisting.

“The Boulder Mountain area has been closed off to assist with the rescue effort and we request that the general public keep the area and nearby highways clear for the ongoing rescue effort,” said Moskaluk.