Moscow (CNN) -- Wigs, dark glasses, a compass and a large bundle of foreign cash -- it's the stuff of any Cold War-era spy novel.
That's the "spy arsenal" Russia's counterintelligence agency says it found with a U.S. diplomat when he was caught allegedly trying to recruit a Russian special services staff member.
The diplomat in question, Ryan Fogle, third secretary of the Political Department of the U.S. Embassy in Moscow, was declared "persona non grata" Tuesday.
Russia's Foreign Ministry has demanded his "early expulsion."
Fogle was detained overnight Monday to Tuesday "during an attempt to recruit a representative of one of the Russian security services," the Foreign Ministry statement said.
He was briefly held before being handed over to the embassy, following formal protocol, Russia's counterintelligence agency, the FSB, said earlier.
"The 'spy arsenal' that was found with him -- as well as a big sum of money -- not only expose a foreign agent who was caught red-handed but also raise serious questions for the American side," the Foreign Ministry said.
"While the presidents of our countries reaffirmed their readiness to expand bilateral cooperation, including the cooperation of intelligence agencies in fighting international terrorism, such provocative actions in the spirit of the 'Cold War' does not contribute to building mutual trust."
The U.S. diplomat had "special technical devices, written instructions for the Russian citizen being recruited, a large sum of cash and means of changing his appearance," state news agency RIA-Novosti quoted the FSB as saying earlier Tuesday.
An image released by the FSB shows what it says are his belongings, including two wigs, a knife, two pairs of dark glasses, a map and a compass.
Another shows what appears to be a large quantity of high-denomination euro currency notes.
The man, with short brown hair and wearing a blue-and-white-checked shirt, is also pictured apparently being detained by security in the street and seated at a desk for questioning.
A photograph of the man's ID card released by the FSB identifies him as Ryan Fogle.
Nikolai Zakharov, a spokesman for the FSB, said the Russian approached by Fogle was free and that there were no charges or accusations against him.
The Russian report of what happened makes the case sound closed, but a former FBI counterintelligence officer cast doubt on that account.
"I very much doubt that a highly trained CIA operative is going to be walking the streets of Moscow wearing a really bad blond wig. It's poor trade craft, and it looks like a setup to me," said Eric O'Neill.
He suggested that the Russians likely planted the material on Fogle for dramatic effect, perhaps to stir up anti-American sentiment, achieve a political objective, or distract attention from some other matter.
The Russian Foreign Ministry said it had summoned U.S. Ambassador to Russia Michael McFaul for an explanation.
The embassy did not comment Tuesday.
U.S. State Department spokesman Patrick Ventrell told reporters in Washington that an officer at the Moscow embassy was briefly detained and released.
He declined to comment further.
It's not the first time in recent years that Russia and the United States have traded claims about alleged agents, in episodes reminiscent of the Cold War era.
In 2010, the two nations carried out a "spy swap" in Vienna.
The United States exchanged 10 Russian agents who had been expelled for intelligence gathering for four individuals who had been incarcerated in Russia.
CNN's Alla Eshchenko reported from Moscow, Nick Paton Walsh reported in London, and Laura Smith-Spark wrote in London. CNN's Brian Todd also contributed to this report.