At Least 5 Dead After Whale Watching Tour Boat Sinks Off British Columbia

— -- At least five people died after a tour boat with 27 people on board sank off the coast of British Columbia Sunday, Canadian officials said.

The boat, reportedly a whale watching tour boat, sank off Tofino, British Columbia, west of Vargas Island, according to the Joint Rescue Co-ordination Centre in Victoria. The center said it received a mayday call from the boat at around 4 p.m. PT.

According to Acting Sub-Lieutenant Melissa Kai with the Joint Rescue Coordination Center in British Columbia, five people have died and 21 people were rescued, with one person still missing. That case involving the unaccounted person, she said, has been turned over to the RCMP.

Kai said that the boat, the Leviathon II, is partially submerged, with the bow sticking out of the water.

She also said the cause of the capsize is currently being investigated.

An Island Health public information officer earlier told ABC News that eight people are in Tofino Hospital: seven in stable condition, and one in serious but stable condition.

The exact number of people in hospitals is unknown, according to Jenn Hamilton, a spokesperson for British Columbia Ambulance Services, adding that five ambulance crews were sent altogether, and that off-duty paramedics helped at the scene as well.

CTV News reported that the ship belongs to Jamie's Whaling Station and Adventure Centres, which offers whale watching cruises.

Jamie's Whaling Station and Adventure Centres issued a statement, calling what happened a tragic day:

"Our entire team is heartbroken over this incident and our hearts go out to the families, friends and loved ones of everyone involved.

"We are doing everything we can to assist our passengers and staff through this difficult time.

"We are cooperating fully with investigators to determine exactly what happened."

Rachel Katz, Joshua Hoyos and Jessica Church contributed to this report.

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