KIEV, Aug 31 (Reuters) - A Ukrainian naval vessel in the Azov Sea was attacked by artillery from the shore on Sunday, and a rescue operation was under way, a military spokesman for the Ukrainian government said.

Andriy Lysenko said the vessel was a naval cutter. There was no information on the number of people on board.

Pro-Russian rebels claimed responsibility for the attack on social media.

(Reporting by Pavel Polityuk and Aleksandar Vasovic; writing by Mark Trevelyan; editing by Andrew Roche)

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