The state-run TASS news agency identified the man as Paul Whelan. A criminal case has been opened against him.
Russias Federal Security Service (FSB) said on Monday that it has detained a U.S. citizen on suspicion of espionage.
Camera Icon Russian President Vladimir Putin and US President Donald Trump attend a meeting in Helsinki
Russian President Vladimir Putin chairs a Security Council meeting in the Kremlin in Moscow on Friday. No other details were given.
The investigation, however, is still ongoing according to the Ministry, and it doesn't appear as though formal charges have yet been brought.
News of the detention comes shortly after Russian President Vladimir Putin said Russia is "open to dialogue" with the US in a holiday message to President Donald Trump on Sunday.
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Graham said that while the president had not committed to the deal proposal, it was the "outline of a potential breakthrough". The White House has dropped its request further to $2.5 billion, but Democrats are holding the line against funding the wall.
Under Russian law, convictions in spying cases can carry prison terms of up to 20 years.
The detention of Whelan comes weeks after a Russian woman pleaded guilty in a US court to acting as an agent for the Kremlin.
American authorities detained and charged Russian national Maria Butina with spying earlier this year.
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Each member of the FAANG cohort rallied at least 6.4 per cent, while energy producers surged as crude powered past US$46 a barrel. The S&P 500 is down 7.7 percent and is on pace for its first annual loss in a decade after including dividends.
The agency said the American was detained "while carrying out an act of espionage".
"We are aware of the detention of a USA citizen by Russian authorities", a press officer for the State Department in Washington said by e-mail on Monday.
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He had campaigned on the promise of building the wall, and he also promised Mexico would pay for it. Schumer and Pence met Saturday at the request of the White House, according to Schumer's office.