The bus and a truck were travelling from Winnipeg, where Twain performed on Tuesday, to Saskatoon - a drive lasting around nine hours.

The two concerts were part of the star's Queen Of Me tour.

Maverick Management told the PA news agency one crew bus and one truck from the tour were involved in a "highway accident".

"Multiple vehicles encountered dangerous driving conditions due to inclement weather," a spokesperson said.

"Members of the production crew who require medical attention have been taken to nearby hospitals."

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The firm added: "We are incredibly thankful to the emergency services teams for their quick response and ongoing support.

"We ask for patience as we look after our touring family."

Twain is expected to perform at the Sasktel Centre in Saskatoon on Thursday evening.

The 58-year-old has four dates left to perform in Canada before her third Las Vegas residency from May to December next year.