Evoking the spy games of the Cold War, Russia said Tuesday that it had detained an American diplomat who was carrying cash, two wigs and technical equipment and was trying to recruit a Russian intelligence official to work for the CIA.

Russia ordered the expulsion of the American diplomat, whom it identified as Ryan Christopher Fogle, third secretary of the political division of the U.S. Embassy. The State Department said only that an officer at the U.S. Embassy in Moscow had been detained and released.

American officials said they did not expect a rift in U.S.-Russian relations. U.S. officials are trying to improve those relations, and to persuade Russia to help resolve a civil war in Syria.

FSB via AP

Wigs and spy gadgets that the Russian Federal Security Service says were carried by American diplomat Ryan Fogle.

Russia used stronger language, calling the matter provocative and in the spirit of the Cold War.

A statement by the Russian Federal Security Service, the successor agency to the Soviet-era KGB, said that Fogle was taken to the service’s headquarters and then to the U.S. embassy after his arrest Monday night.

The security service, known as the FSB, released to Russian media photographs of the American’s arrest and what it said were items he had with him, including the wigs, a torch, a compass and a wad of 500-euro notes, each worth $650.

Russian television also displayed a letter it said was found on Fogle, printed in Russian and addressed “Dear friend.” The letter offered a $100,000 payment as “an advance from someone who has been highly impressed by your professionalism, and who would highly value your cooperation in the future.”

The statement from the security service said that the U.S. had “repeatedly attempted to recruit employees of Russian law enforcement bodies and special departments” recently.

The U.S. ambassador to Russia, Michael McFaul, was participating in a question-and-answer session on Twitter when the detention was announced. He was summoned to Russia’s foreign ministry, The Associated Press reported.

Experts expressed surprise at the old-school nature of the alleged espionage, but they noted that intelligence-gathering had not stopped just because the Cold War ended more than two decades ago.

FSB via AP

In this photo provided by Russian Federal Security Service, a man claimed by the service to be Ryan Fogle is seen at the service's offices in Moscow.

“If anything, it has increased,” said James Nixey, head of the Russia and Eurasia Programme at the British think tank Chatham House. “The methods have changed — or so we thought — because it’s more about industrial espionage and corruption these days.”

Besides the diplomacy over Syria, there have been questions about whether Russia gave the United States enough information about Tamerlan Tsarnaev, one of the suspects in the attack on the Boston Marathon.

Russian officials asked the U.S. for more information about Tsarnaev, who was born in what is now Russia and traveled to Russia early last year. Russia suspected that Tsarnaev was becoming radicalized, American officials have said.

The FBI interviewed him in 2011 and turned up nothing, and when the FBI asked Russia twice for more information about its concern, Russia failed to respond, the American officials said. Tsarnaev was killed April 19 in a shootout with police.

President Barack Obama later said Russia had cooperated since the attack but noted: “Old habits die hard. There are still suspicions sometimes between our intelligence and law enforcement agencies that date back 10, 20, 30 years, back to the Cold War.”

The incident would not be the only intelligence blunder in Russia. Britain admitted bugging a Moscow park in 2006 by disguising a recording device as a big rock. The FSB saw a British diplomat picking it up and walking away with it.

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Editor’s note: This story includes a correction.

This story was originally published on Tue May 14, 2013 7:59 PM EDT