The former chief of the Investigative Committee's internal security, Mikhail Maksimenko, was found dead at Correctional Colony No. 11 in the Nizhny Novgorod region, local media reported on November 21.
Maksimenko's lawyer, Andrei Grivtsov, confirmed to the Vedomosti newspaper that his client was found dead but refused to give any details.
The Mash Telegram channel said Maksimenko's body was discovered at the prison's psychological treatment unit. Unconfirmed reports said Maksimenko died by suicide but did not specify how.
Meanwhile, a source close to Russia's Federal Penitentiary Service (FSIN) told RBK news agency that Maksimenko was attending psychological treatment courses at the unit after an attempted suicide.
Prison officials have not commented publicly on the matter.
A member of Russia's presidential Human Rights Council, Yeva Merkachyova, expressed concern about Maksimenko's death, calling it "strange."
According to Merkachyova, she visited Maksimenko when he was held at the Lefortovo detention center in Moscow before and during his trial. Merkachyova stressed that Maksimenko was held in the "worst, cold cell," and "was afraid of possible poisoning."
"He also said that he would never commit suicide. And therefore, his death looks even more strange," Merkachyova said on Telegram.
Maksimenko was arrested in 2016 on suspicion of obtaining a bribe from a notorious criminal kingpin, "thief-in-law" Zakhary Kalashov, known among criminal circles as Shakro Molodoi. "Thief-in-law" is the highest title in the criminal hierarchy traditionally given to kingpins among criminal groups in former Soviet republics.
Investigators said at the time that Maksimenko, along with the former chief of the Investigative Committee's Moscow branch, Aleksandr Drymanov, and several other top investigators received $1 million for assisting to get a criminal kingpin Andrei Koichukov, known under nickname Italyanets (Italian), released.
Koichukov was then in pretrial detention for alleged involvement in a shoot-out in Moscow related to a high-profile extortion case.
In 2018, a court in Moscow sentenced Maksimenko to 14 years and Drymanov to 12 years in prison after finding them guilty of abuse of office and bribe-taking. Two other defendants in the case, the Investigative Committee's top officers, Aleksei Kramarenko and Denis Nikandrov, were sentenced to 10 and 5 1/2 years in prison, respectively, on the same charges.
Nikandrov pleaded guilty and testified against other defendants in the case.
Maksimenko maintained his innocence.
Last week, Kramarenko's lawyer, Ivan Mironov, said his client was pardoned by President Vladimir Putin after the Defense Ministry had recruited him from a penal colony six months earlier to the ongoing war in Ukraine.