Russian Federal Security Service FSB said it had "stopped the illegal activities" of a Russian citizen operating as an informant working for the US embassy in Moscow and charged him with treason for working on behalf of a foreign state.

Robert Shonov, a former employee of the US Consulate General in Vladivostok, was apprehended last March and accused of collaborating with two American diplomats to undermine Russia's national security in exchange for material rewards.

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"The Russian Federal Security Service stopped the illegal activities of an informant of the US Embassy in Moscow, a former employee of the US Consulate General in Vladivostok, Russian citizen Shonov Robert Robertovich, he was charged with committing a crime under article 275.1 of the criminal code of Russia 'Cooperation on a confidential basis with a foreign state,'" the FSB said.

According to the security agency, the informant carried out tasks on behalf of embassy diplomats between September 2022 and his arrest in March 2023. The FSB identified the US embassy employees as Jeffrey Sillin and David Bernstein.

Shonov was tasked to "collect information on the progress of the special military operation, mobilization processes in the regions of Russia, on problematic moments and assess their influence on the protest activity of the population on the eve of the presidential elections in Russia in 2024," the statement read.

The intelligence agency also confirmed that it plans to interrogate the US staffers and that it issued subpoenas to the US embassy.

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