The Canadian documentary filmmaker and conservationist Rob Stewart disappeared while diving off Florida’s southern coast during the filming of a movie about sharks, the US Coast Guard reported Wednesday.

Stewart, 37, vanished Tuesday afternoon during a dive with three of his crew members at the Alligator Reef coral reef, some 4 nautical miles (seven kilometers) off the island of Islamorada.

The US Coast Guard issued a statement saying it had received a report of a missing diver shortly after 5 pm (2200 GMT).

The Navy, police and Florida wildlife conservation commission are assisting the search, it added. 

The reason for Stewart’s disappearance remains unknown. Resurfacing at the end of his dive, he went underwater again before the crew’s boat was able to pick him up. The other three divers emerged safely.

The particularly deep and difficult dive was his third of the day, his sister Alexandra Stewart told the state broadcaster CBC, adding that another crew member appears to have temporarily lost consciousness when he resurfaced.
 

 
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