It is a document that tells of horror, arbitrariness, detention of forcibly displaced civilians in camps and other violations of international humanitarian law in the Russian-occupied territories of Ukraine. In its latest report 'We Had No Choice' — 'Filtration' and the Crime of Forcibly Transferring Ukrainian Civilians to Russia, released on Thursday, the rights group Human Rights Watch has interviewed 117 eyewitnesses, most of whom had to go through the so-called "filtration process" used by Russian security authorities and their allies in eastern Ukraine.

Thousands of civilians fleeing the war were detained, sometimes for days — especially after the Russian army captured southern Ukraine and the city of Mariupol in the spring. The report details how they were interrogated for hours to "filter out" Ukrainian servicemen and women. During this screening, security guards "collected civilians' biometric data, including fingerprints and photographs of their face looking forward and in profile," said the HRW report.

Contact details were copied from the civilians' smartphones, and their private text messages and comments on social media channels were also examined. The eyewitnesses quoted in the report independently confirmed the locations of the camps and procedures carried out there, and recounted the same events.

Hours of interrogation

HRW investigators conducted the interviews, some of them by telephone, between March 22 and June 28. Some of the interviewees now live in Norway, Germany and other western countries after fleeing via Russia. Seventy-eight of those interviewed were able to escape past numerous Russian military checkpoints into unoccupied territory near the city of Zaporizhzhya, in southern Ukraine.

The government in Kyiv believes 1.2 million of its citizens have been taken to Russia. Some of them were forcibly removed, while others had given their consent but mostly because no other option was open to them, HRW said. For many, detention and "filtration" are the first step in their escape from war. This procedure is in violation of the Geneva convention on human rights.

"Herding people further into Russian-occupied areas and onward to Russia without consent should immediately stop," said senior researcher Belkis Wille, who compiled the report. "Russian authorities and international organizations should do everything they can to help those taken to Russia against their will who want to return home to be able to do so safely."

The organization had asked Moscow for comment before the report was published, but received no response.

Standing in line for 10 days to be interrogated

A woman from the village of Melekyne, south of Mariupol, described how she and her husband initially left their home on foot in mid-April. They walked to the village of Manhush, where they were held by pro-Russian separatists of the self-declared Donetsk People's Republic. There, they had to stand in line for 10 days waiting to be interrogated.

"Basically, you go and stand in a queue all day, and then at night when it’s curfew time you go back to where you are staying, and you do the same again the next day," the woman said.

A man from Mariupol recounted how he was detained with "dozens" of other people from his town for two weeks in a village school in disastrous sanitary conditions before the interrogations began. "We felt like hostages," this witness said.

Individuals who "failed" the procedure because they appeared to have links to the Ukrainian military or nationalist groups were detained in Russian-controlled regions, including the detention center in Olenivka, where at least 50 Ukrainian prisoners were reportedly killed in an explosion on July 29, the report said.

Others were reportedly taken to the prison at the Izolyatsia industrial site near Donetsk, which was set up when fighting began in eastern Ukraine in 2014. In total, Human Rights Watch has recorded 15 interrogation and detention centers on Russian-occupied territory.

But the report is only the latest of several showing evidence of the Russian internment and filtration system in Ukraine.

More than 20 filtration camps

At the end of August, Yale University published an analysis of the "filtration system" , working with publicly available sources such as news and videos from messenger services and social media channels and with satellite images showing at least 21 camps.

The researchers divided these camps into four categories: centers for "registration," centers where the displaced civilians were forcibly detained pending interrogation, centers for repeat interrogations and, finally, internment camps. "In some specific instances, the treatment described as having been endured by those released, such as use of electric shocks, extreme conditions of isolation, and physical assault, may potentially constitute torture if proven," the report said.

In addition, there is "evidence that the system was created weeks before the invasion began and likely grew following Russia's capture of Mariupol in April 2022 to accommodate filtration of all citizens."

There is no trace of many detainees. According to the International Commission on Missing Persons in The Hague, Ukrainian police have so far registered 32,000 missing persons, and to date, 14,500 people are registered as missing, which includes many of those who are still detained.

The nongovernmental organization was founded in the 1990s to identify the missing from the war in the Balkans, particularly after the massacre of more than 8,000 boys and men in Srebrenica. The remains of tens of thousands of missing persons from the Yugoslav wars have been recovered from mass graves over the past 25 years and matched to their relatives using genetic analysis.

"We are also trying to help Ukraine," said ICMP Director-General Kathryne Bomberger in an interview with DW. The aim, she said, is to "identify cases of missing persons and investigate them according to judicial standards that make it possible to hold the perpetrators of atrocities accountable in court."

The researchers at Yale University expect more human rights violations will come to light. Several of the satellite images they analyzed show excavations in at least two Russian internment camps — for the researchers, a clear indication of further mass graves in the south and east of Russian-occupied territories in Ukraine.

This article was originally written in German.

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