A former top official in the Russian prison service shot and killed himself in a Moscow court on Wednesday shortly after being jailed for extortion, a court spokeswoman said.

Viktor Sviridov, who previously headed the prison service's transport department, "committed suicide in the courtroom by shooting himself in the chest", a spokeswoman for Moscow City Court told AFP.

Sviridov, 71, had pleaded not guilty to extorting 10 million rubles ($159,000) from a former deputy director of the prison service. He was found guilty and sentenced him to three years in a penal colony.

As police walked over to arrest him following sentencing at the Chertanovo district court, he drew the pistol and shot himself. He died at the scene.

His sentence was less than the maximum possible term of 15 years because he had been diagnosed with advanced cancer, Russian media reported.

Viktor Sviridov is one of several officials who have killed themselves following investigations into corruption in Russian prison service
Viktor Sviridov is one of several officials who have killed themselves following investigations into corruption in Russian prison service AFP / Dimitar DILKOFF

It was unclear how the former official, who had been living at home while subject to a travel ban, managed to take a gun into the Chertanovo district court despite metal detectors at the entrance.

The Investigative Committee, which probes serious incidents, said it was looking into possible criminal negligence and would check "metal detectors at the entrance to the court building, designed to detect banned objects."

Ren-TV channel aired what it said was security camera footage of Sviridov going through the metal detector and showing his bag to court bailiffs before being allowed through.

The pistol Sviridov used was given to him as an award, investigators said in a statement. Sviridov had served in the police before working in the prison service for several years.

Investigations into corruption in the prison service have uncovered rampant violations involving officials and several have killed themselves.

Viktor Sviridov is one of several officials who have killed themselves following investigations into corruption in Russian prison service
Viktor Sviridov is one of several officials who have killed themselves following investigations into corruption in Russian prison service AFP / Kirill KUDRYAVTSEV

In 2012, the former deputy head of the far eastern Khabarovsk region's prison service committed suicide while facing accusations of corruption. His predecessor had killed himself six months earlier, also while facing fraud charges.

A former head of the prison service, Alexander Reimer, was sentenced to eight years in 2017 for embezzling millions of dollars of state funding allocated to buy electronic bracelets.

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