Russia’s domestic security service has detained a US citizen it claims was on a “spy mission” in Moscow.
The FSB said the American, named Paul Whelan, was detained on Friday “during an espionage operation”, but did not give any further details.
A criminal case has been opened against him, the agency added in a statement on Monday.
A police statement read: “On December 28 members of the federal security services of the Russian Federation arrested US citizen Paul Whelan in Moscow for carrying out espionage.”
If found guilty he faces up to 20 years in prison.
The arrest comes as Russia-US ties have sunk to post-Cold War lows over the Ukrainian crisis, the war in Syria and the allegations of Russian meddling in the 2016 US presidential election.
Earlier this month, a woman suspected of being a Russian secret agent in the US began cooperating with federal prosecutors after agreeing to a plea deal.
Maria Burtina, 30, admitted engaging in a conspiracy against America to try to gain influence in US politics through the National Rifle Association.
The US embassy in Russia was unavailable for comment. The state department has been contacted for comment.
