EDMONTON (AP) - A blizzard sweeping across the Canadian plains caused a chain of traffic crashes south of Edmonton, Alberta, injuring about 100 travellers, officials said on Thursday.

One person was seriously hurt and about 80 were treated at the site, said Mr Kerry Williamson of the Alberta Health Services office.

Another official had earlier estimated that 300 people were hurt, four seriously. About 22 people were taken to hospitals in nearby communities, Mr Williamson said.

The Royal Canadian Mounted Police (RCMP) closed part of Highway 2, the main road between Edmonton and Calgary, and were directing traffic away from the collision scene, said RCMP Staff Sgt. Grant MacDonald.

He said the crash involved several vehicles, including a large passenger bus and several semi-trailer trucks.