Russia’s security agency, FSB, on Monday said it has arrested an American citizen in Moscow accused of spying, AFP reported. The FSB in a statement said the American, identified as Paul Whelan, was arrested on Friday “while carrying out an act of espionage”.

The statement said a criminal case has been registered under Article 276 of the Russian Criminal Code, which allows for sentences up to 20 years in prison.

The arrest comes amid the conviction of Russian citizen Maria Butina in the United States for acting as a Russia state agency, infiltrating conservative political groups, BBC reported.

In November, the US had said it planned to impose additional sanctions on Russia as it believes Moscow has failed to give reasonable assurances that it will not use chemical weapons. The US had threatened the sanctions after Russia allegedly used a nerve gas agent in an attempt to poison former double agent Sergei Skripal and his daughter Yulia in England. Russian President Vladimir Putin has repeatedly denied allegations that Moscow was responsible for the attack.