Sergey Vladimirovich Cherkasov

Sergey Vladimirovich Cherkasov (, ), also known as Victor Muller Ferreira , Cherkasov first arrived in Brazil in 2010 under his real Russian name. After this, he managed to get legitimate Brazilian documents with a fake birth certificate under the name "Victor Muller Ferreira". He used the name of a fake father and the name of a deceased woman who actually didn't have any children in the fake birth certificate. Under that false identity, he managed to get Brazilian documents and a Brazilian passport, which he used to enter and leave Brazil with. He left and returned to Brazil 15 times from 2010 until 2022.

The Dutch Military Intelligence and Security Service published a document in broken Portuguese that they stated was his cover story.

Operating under his fake Brazilian identity,

At the time of his hiring, the ICC had begun to investigate war crimes committed by the Russian military in Ukraine. He added "Essentially these are sleeper agents. The idea would be that - from a young age- they would build up a fake identity, and they would acquire different qualifications and credentials that would make them more plausible. Then they will be used to infiltrate Western organisations. Trinity College would be a very credible university based in a friendly western country. So from that perspective, placing an operative in Trinity and giving them a background there would be something that can be utilised later." but the sentence was later reduced to 5 years and 2 months. In July 2023, Brazilian authorities have declined a US request to extradite him, saying that he would eventually be sent to Russia instead. In a statement, the Brazilian Ministry of Justice and Public Security said that the Federal Supreme Court approved a request by Russia to extradite him to Russia on 17 March 2023, where he is accused of “drug trafficking,” according to Russian state-run news agency TASS.

Money laundering charge In January 2024, Brazil brought a new charge against Cherkasov, with the accusation that he had received and laundered money from Ivan Chetverikov, a Russian diplomatic employee at a mission in Brazil; the charge reportedly will prevent Cherkasov's eligibility for early release from imprisonment on his earlier conviction.