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Authorities told Canadian news outlets a search and rescue mission was underway.

Rescuers said there were 27 people on board when the boat, from Jamie's Whaling Station and Adventure Centres, sank. Officials told The Associated Press that 18 people were hospitalized in stable condition.

The Joint Rescue Coordination Centre in Victoria received a mayday call from the boat around 4 p.m. PT.

>> Click here or scroll down to see images from the scene

This video includes images from Rami Touffaha Burnaby Tours and Charters.