MOSCOW (Reuters) – Russia’s foreign Ministry said on Thursday it would issue an official protest note to the U.S. Embassy in Moscow after authorities caught three U.S. diplomats in a restricted area near a secret test site, TASS reported.

Diplomats, among them U.S. military and naval attaches, were removed from a train Monday in Northern Russia near the site of a mysterious military accident that occurred in August.

A U.S. state Department spokesman said the diplomats were on an official trip and that they had notified Russian authorities in advance of their travel plans.

However, the Russian foreign Ministry said the diplomats were found in a restricted area more than 40 kilometers from the city of Arkhangelsk, which they said they planned to visit.

Reporting by Anton Kolodyazhny; writing by Tom Balmforth; editing by Andrew Osborn

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