By Jake Tacchi and Victoria Arakelyan
BBC Eye Investigations
A Russian police officer's takeaway food order was the breakthrough clue which helped a group of women, who had been terrorised by him, reveal his true identity. For the first time, a BBC investigation tells the story of how they tracked him down.
The women, mostly aged between 19 and 25, had attended a rally in Moscow in March against Russia's invasion of Ukraine. They were quickly rounded up by officers and put in the back of a police van.
Most of them didn't know each other, but despite the circumstances the atmosphere was upbeat. They even set up a Telegram group chat as they travelled across the city to Brateyevo police station.
What happened next was far worse than they anticipated.
Over the next six hours they suffered verbal and physical abuse that, in some cases, amounted to torture – one woman says she was repeatedly starved of oxygen when a plastic bag was put over her head.
The abuse was carried out by the same unnamed plain-clothes officer – tall, athletic, dressed in a black polo neck. In their group chat, they gave him the nickname the "man in black".
Two of the women, Marina and Alexandra, secretly recorded audio on their phones. In one, the officer can be heard shouting about his "total impunity".
But if his aim was to intimidate them into silence, he would fail.
This video can not be played
Listen to the “man in black” shouting insults at Marina and Alexandra while he assaults them
After their release, the women discussed on the Telegram group how they could work out who he was.
"If we just kept on living like it didn't happen, if we just published the [recordings] and laid low… most likely, they would think they can do it again and that they would be completely unpunished," says 22-year-old student Marina.
His image was seared in their memories, but they could find no sign of him on police websites. And with no name to go on, social media was a dead end. After more than a fortnight of searching, they were close to giving up.
And then the women had a breakthrough.
In late March, there was a massive data leak from the popular Russian food delivery app Yandex Food. The group had an idea.
They began raking through the data to see if there had been any orders to Brateyevo police station over the past year. They discovered there had – by nine different customers. Could one of them have been the "man in black"?
Most of the Yandex data only included first names and a phone number. The group of women used these to find several social media profiles for staff at the police station, but no photos resembled their interrogator.
Finally they came to one of the last names on the list: Ivan. A popular Russian name, so one of the most difficult to pin down. Ivan's phone number, however, did reveal a trail online – six classified adverts from the Russian trading website Avito.ru. But most of the adverts only gave them the information they already knew – a first name.
One, however – for a Skoda Rapid car sold 10 minutes' drive from Brateyevo police station, posted in 2018 – included the seller's full name: Ivan Ryabov.
With a surname, they could search for a picture. And almost immediately, 19-year-old Anastasia came across one she recognised.
"I started crying. I could not believe… that I managed to do it."
She sent the picture to Marina, Alexandra, and others in the Telegram group, who agreed they had found their "man in black".
They hope this will finally prompt the authorities to open a criminal investigation.
The audio recordings give a chilling insight into the women's abuse.
Ryabov can be heard telling Marina to answer his questions before "I take off my boot and smash you on the head with it."
For 14 minutes, Marina says she was shouted at and kicked by Ryabov – a pistol in her face.
Finding My Torturer
BBC Eye Investigations tells the story of how these young Russian women came together to expose the identity of their torturer and his commanding officer.
Watch now on BBC iPlayer (UK Only)
Anastasia, waiting outside, remembers hearing the sound of screaming and blows. When she, too, refused to co-operate with the questioning, she says Ryabov beat her over the head with a water bottle, emptied its contents over her, and then pulled a plastic bag over her soaking head where he held it against her nose and mouth for 30-40 seconds at a time.
"You think to yourself – how much longer can I take this?" she says.
Alexandra, 26, also managed to record her abuse, and in her audio we hear Ryabov boast of his total impunity. "You think we're going to get in trouble for this? Putin told us to kill all of [your type]. That's it! Putin's on our side!"
He then threatens to kill her himself, adding: "And then they'll give me a bonus for it too."
At least 11 of the detainees say they experienced physical abuse at the hands of the "man in black".
When the women publicly released the audio recorded on their phones earlier this year, one Russian politician called for action – but the country's Investigative Committee deemed there to be "insufficient evidence" to warrant opening a criminal investigation into the case.
The women also wanted to know who had authority over Ryabov that day – and why that person wasn't stopped.
Anastasia had always felt another man – who the women dubbed the "man in beige" – was in charge that evening. Though he wasn't present inside Room 103 – where the women were terrorised – "all communication took place through him", she says.
One of the detainees had secretly filmed him in the station waiting room. But the shaky video wasn't much to go on.
The BBC obtained an arrest report from 6 March, which was signed by the police station's acting head: Lieutenant Colonel AG Fedorinov.
We then found a local newspaper report from 2012 which mentions an Alexander Georgievich Fedorinov, with an accompanying photograph which seemed to match his image.
But because the photo was 10 years old, the BBC used facial recognition software to double-check – and found images matching the "man in beige" in the video were linked to a social media account in the name of Alexander Fedorinov. That same account was tagged in an online advert for job vacancies at Brateyevo police station.
The BBC put the allegations – that police officer Ivan Ryabov initiated and participated in the abuse of detainees, and that this abuse in some cases amounted to torture – to both Ryabov and Fedorinov, and to Russia's Investigative Committee. There was no response.
By uncovering the identity of their abuser, Marina, Anastasia and Alexandra hope that some form of justice and accountability will emerge.
"We want to make… it possible for the law to affect them," says Marina. "No one can do this to another person, even if he is a government official."
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By Jake Tacchi and Victoria Arakelyan