Russian intelligence agents have tried to recruit sources from churches in the United States, leading to an intervention by the FBI, according to a recent story.

The September 14 story in Foreign Affairs detailed how the FBI warned Russian Orthodox and Greek Orthodox Christian parishes about possible efforts of Russian spies to use their churches for recruitment. One suspected Russian agent was allegedly willing to blackmail church members.

Orthodox Christianity is a popular religion in Russia and Ukraine, but especially in Russia. The Russian branch of the church has also publicly supported Russian President Vladimir Putin’s invasion of Ukraine, which has caused friction with parishes all over the world. Russian Orthodox Church leader Patriarch Kirill has also stirred controversy for his ties to Putin, as well as for a sermon that urged mobilized troops to “go bravely to fulfill your military duty.”

Andrei Soldatov and Irina Borogan wrote that they reviewed FBI documents that “identify and highlight the activities of a senior member of the Russian Orthodox Church’s foreign relations department whom the FBI suspects of having ties to Russian intelligence.”

“The FBI’s warning suggests that the church may be even more closely linked to the Putin regime than many observers assume, with potentially significant implications for the Kremlin’s overseas influence,” they wrote.

“The documents identify and highlight the activities of a senior member of the Russian Orthodox Church’s foreign relations department whom the FBI suspects of having ties to Russian intelligence.”

Newsweek could not verify the contents of the FBI documents, and the agency did not directly address the warning when contacted for comment.

“While we have no comment on the specifics of your inquiry, the FBI regularly meets and interacts with members of the community,” the FBI told Newsweek in a statement. “We do this to enhance public trust in the FBI, to enlist the cooperation of the public to fight criminal activity, to provide information in support of crime prevention efforts, and to open lines of communication to help make the FBI more responsive to community concerns.”

Per Foreign Affairs, the FBI warning said there were reasons to suspect that a senior official in Russia’s Department for External Church Relations who recently traveled to America was a “Russian Intelligence Officer operating under non-official cover.”

“His objective in the United States, according to the warning, was to recruit the clergy of the Russian Orthodox Church and other Orthodox churches,” Soldatov and Borogan wrote.

The official was reportedly stopped and searched by U.S. Customs and Border Protection officers when he arrived in the United States in 2021. He was said to have been in possession of documents related to Russia’s foreign intelligence service and its military intelligence agency.

The story noted that the official allegedly had files on church members for the purpose of blackmailing them into working for the Kremlin.

“According to the FBI notification, the Russian national was also carrying ‘files regarding the source/agent recruitment process’ as well as dossiers on church employees, including detailed biographical information about them and members of their families—information that the warning suggests could be used to blackmail employees of the church into participating in spy operations,” the story said.

Soldatov appeared on CNN last week to discuss his reporting on the Kremlin’s links to the Orthodox Church in the United States.

He told host Erin Burnett that not only had Moscow agencies “found a way out to use the church, but that the church is apparently quite happy to be used.”

When asked about the size of Russia’s intelligence network in America’s Orthodox churches, Soldatov said that “it is a big platform because the Russian Orthodox Church is very well present here in the United States and actually getting bigger.”

There are more than 2,000 Orthodox Christian parishes in the United States as of 2020, according to usreligioncensus.org.