Updated

Russia is slamming reports that the U.S. is probing accusations that a Russian cultural exchange official has been attempting to recruit young Americans as intelligence assets.

Law enforcement officials confirm to Fox News that the FBI is probing the Rossotrudnichestvo cultural exchange program based in Washington, and run by Yury Zaytsev, and are interviewing Americans who have participated in it.

For the past 12 years the program has been paying for Americans to visit Russia, and the center also offers language lessons and cultural programs.

The Russian Foreign Ministry said Thursday it was "bewildered" by the allegations and said the "fabrications they contained had nothing to do with the reality."

It demanded the U.S. government "unequivocally and publicly disavow the ill-intended attempts to cast a shadow on the activities of the Russian Center for Science and Culture."

Zaytsev was quoted by Russia’s Itar-Tassnews agency as saying, “It’s a shame that echoes of the Cold War are heard in Russian-American relations from time to time.”

Zaytsev’s immigration status in the U.S. has not changed, and he has not been asked to leave the country, officials say.

Richard Portwell, the executive director of the Center for American-Russian Engagement of Emerging Leaders, is one of the people the FBI has interviewed in connection with the case. He tells Fox News in his dealings with Zaytsev he has never experienced any activities like the allegations suggest.

Zaytsev's case comes amid friction in U.S.-Russian ties, which have been strained over differences on Syria, Moscow's decision to give refuge to former National Security Agency systems analyst Edward Snowden and the Kremlin's crackdown on the opposition and rights activists.

A flurry of spy cases has added to the tension. In May, Russian security services arrested a U.S. diplomat who they say was caught red-handed while trying to court a spy. He left the country a few days later.

In 2010, the FBI busted a ring of sleeper agents for Russia that it had been following for years in the United States. All 10, including the now well-known Anna Chapman, pleaded guilty and were returned in a swap.