Russian authorities said on Wednesday they had fired five top prison officials and opened a large number of criminal investigations into allegations of torture and sexual assault at a prison in the Saratov region.

The authorities took this measure after the "Gulago.net" organization concerned with the rights of prisoners began publishing what it said was video evidence of systematic torture practices in the prison, which is located about 70 km southeast of Moscow.

She explained that she had received many leaks of documents, photos and videos that prove that hundreds in the country's prisons were subjected to torture and rape from other inmates under the direction of prison officials.

Vladimir Usishkin, founder of the Gulago.net organization, told Reuters that attacks are taking place in many different places in the country.

He added that the torture system "was and still is in place", and that the authorities "are afraid to admit the truth publicly, and the truth is horrific because the truth is that their own devices are torturing people collectively."

In total, more than 1,000 videos were obtained from the prison system, the German news agency quoted Usishkin as saying.

He added that they confirm the "systematic nature of torture" of prisoners in Russia. Usishkin added that in addition to the video clip of the situation in Saratov, there are also video recordings from penal camps and prisons in the Siberian region of Irkutsk and from Vladimir, near Moscow.

"The video belies those resident deniers who falsify human rights work in Russia and help the security forces cover up the systematic nature of torture in Russia," Usishkin wrote on Facebook.

The video from Saratov shows 4 men being mistreated in a tuberculosis hospital.

According to Julago.net, between January 2020 and May 2021 there were also multiple incidents of sexual violence against prisoners.