Earlier this year, two guards who worked at a prison in Yaroslavl, north-east of Moscow, were jailed for abusing an inmate. Despite official claims that Russian penitentiaries are cleaning up their act, prisoners, their relatives and human rights activists tell a very different story. The BBC's Oleg Boldyrev investigated one recent case.
I haven't seen the room where Roman Sarychev was beaten. Beaten so badly that he died three hours later. No, this is not lazy reporting. The room is inaccessible - behind barbed wire and high walls. But that prison, penal colony number six in the Bryansk region, south-west of Moscow, is known to many people. Some former inmates and even a current one told me exactly what this room looks like and what happens there.
It's windowless, with a low ceiling and walls of glossy yellowish paint. New inmates enter this narrow room through an even narrower corridor leading from the prison entrance. They have to move fast, almost running, bodies bent, handcuffed arms behind their backs. As they move, they are punched, kicked and sworn at by guards while a heavy metal track - Du Hast, by German band Rammstein - plays at ear-splitting volume.
This ritual is called intake. It is designed to frighten and humiliate the new arrivals. Exactly why 32-year-old Sarychev was kicked so hard that his spleen ruptured, is still unknown - an investigation is now under way. But the beating itself is no surprise for those who are familiar with colony number six, or with many other Russian prisons.
The prison service officially reported 2,700 deaths in custody last year. The assumption is that many were from natural causes, but accusations of beatings and torture are commonplace.
A notorious video emerged in 2018 of guards beating an inmate in a prison in Yaroslavl while he was pinned face down to a table.
A year later, several inmates in a prison in Karelia, near the Finnish border, told of beatings and abuse which resulted in at least one death. The prison's former director was jailed last year for torturing inmates. In 2015, five young prisoners were made to urinate on each other then beaten in a prison in Krasnodar, in the south of Russia. One of them died.
These and many other stories often only become public months or years later, once the witnesses have been released. If there's a really big scandal, some prison officers may end up in court. Authorities say lessons have been learned, but similar incidents keep happening.
The incident from Yaroslavl was unusual because there was footage from cameras that are supposed to be worn by guards on duty. Most of the time, though, something happens with the cameras - they just stop working, as indeed was the case with the attack on Roman Sarychev in penal colony number six.
Sarychev had been found guilty of organising a string of illegal internet casinos in Bryansk. He'd hoped to get off with a heavy fine but was sentenced to two-and-a-half years instead. He appealed, hoping that his severe liver condition might mean a non-custodial sentence, but no such luck. Sarychev was transferred to the penal colony at 19:40 on 8 December last year. An ambulance was called an hour later. He then died on the operating table at 22:40.
The following morning Sarychev's mother, Elena, called the prison service, expecting to get the results of his blood tests. Instead a clerk informed her that her son was dead. Elena screamed. Sarychev's sister made another call. She was told there had been "an incident".
Soon after Sarychev died, one guard, Maj Sergei Shevtsov, was arrested. He remains in custody while the investigation continues. Activists who monitor cases of prison violence say it's unlikely that this officer was acting alone.
I talked to the mother of another inmate from the same prison who had arrived just a few hours before Sarychev. She told me that her son, too, was made to run through a line of wardens who punched and kicked him to the sound of that same heavy metal tune.
Other former inmates know Maj Shevtsov well.
One ex-prisoner told me: "He and another guard, nicknamed Smetana, just liked thrashing people. Not to discipline them or to extort money but just because they could."
In July 2018 Smetana, whose nickname means "sour cream" and whose real name is Ivan Marshalko, strangled an inmate with a bed sheet. He is now serving 12 years in prison for this murder. In 2014 another guard, Andrei Yakubov, repeatedly slammed a big stack of books into the head of a prisoner. His victim died a week later from a brain haemorrhage. Yakubov is serving a 10-year jail term.
Penal colony number six has a long history of violence - twice in recent years its prisoners have rioted, protesting against torture and extortion, which was carried out by select gangs of inmates on behalf of the prison administration. People who have done time there told me dozens of deaths were never investigated.
Workers at the mortuary told Sarychev's family that he'd been thrown around "like a rubber toy". His relatives couldn't turn him over to see the other side of his body. But they saw strange round bruises on his legs. They published the pictures online, hoping to shock the public and put pressure on the investigation.
The sad reality, though, is that penal colony number six is far from unique - it's just one prison among hundreds that may hide similar grim secrets.
On the day of the funeral a letter arrived at the home Sarychev had shared with his partner, Maria, and their children. Roman had written it from a remand centre, before he was transferred to the penal colony.
Their five-year-old son dictated a reply. "We also deeply-deeply love you, and we miss our handsome and clever papa," he said. "You were a good papa."
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