The Mounties say three divers from the United States were participating in a recreational dive near Snake Island, a short boat ride from Nanaimo's Departure Bay, on Friday afternoon.
The Dive Industry Association of B.C. says in a news release that the three were participating in a deep dive when "complications arose."
One of the divers made it back to shore and another was confirmed dead on Saturday, leaving the third diver missing.
The RCMP and the coast guard were involved in the search, but those efforts have been called off and the case has now been turned over to the coroner.
Neither the RCMP nor the association has confirmed exactly what went wrong during the dive.
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