Russia’s domestic security service, FSB, said on Monday it had detained an American citizen suspected of spying in Moscow.
The FSB, which said the American was detained on Dec. 28, said in a statement that a criminal case had been opened against him.
It did not provide any detail about the nature of the alleged espionage.
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The U.S. Embassy in Moscow could not immediately be reached for comment.
Russia’s relations with the U. S. have soured since Moscow annexed the Crimean peninsula from Ukraine in 2014.
Since then the U.S. and other Western countries have imposed a wide-range of sanctions against Russian officials, companies and banks.
Reuters/NAN