At least 11 children and their adult instructor have died in a storm while boating on a lake in Russia's northwestern region of Karelia, officials said Sunday.

Vladimir Markin, a spokesman for the nation's main state investigative agency, said several boats with children overturned Saturday in a storm in Syamozero, 120 kilometers east of the border with Finland.

Of 47 children and four adult instructors in the boats, 11 children and one adult have died, Markin said.

He said an instructor has been detained as part of an official probe, suspected of violating safety rules.

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