New findings expose machinery of Russia's "filtration" of Ukrainians

Residents are funneled to registration sites, where they are screened and released or detained. Some Ukrainians have disappeared, according to Human Rights Watch, or were deported to Russia without identification documents.

Ukrainians who go through the system have had their phone contacts downloaded, fingerprints and photographs taken and passport numbers collected, according to the Yale report, which was published last week.

The researchers said they found “with high confidence” that Russian and allied forces in the Donetsk region of eastern Ukraine have used 21 sites for “filtration operations.”

The sites include registration points, temporary holding facilities, interrogation centers and prisons for long-term detention.