Ukrainian president Volodymyr Zelensky warned on Wednesday that two million Ukrainian citizens, including hundreds of thousands of children, have been “forcibly removed” to the interior of Russia since the onset of the Kremlin’s invasion on February 24.

Zelensky drew attention to the issue during his remarks to the Asian Leadership Conference in Seoul. In the same speech, the Ukrainian president warned that the deportees had also been placed in filtration camps within occupied Ukrainian territories in order to determine their sympathies and their willingness to live under Russian rule.

Those determined to be opposed to the Kremlin would be placed in “re-education” camps deep within Russia, Zelensky said. “Just imagine this number—two million people,” he added. “That’s how many of our people have already been taken to Russia. … No one will name the exact numbers at the moment. All these deported people are deprived of means of communications. Their IDs have been taken from them. They are being intimidated and taken to remote areas of Russia, so that it will be as difficult as possible for them to return home to their Motherland.”

U.S. secretary of state Antony Blinken also condemned the deportations, although his estimate of the number of affected Ukrainian citizens was somewhat lower, at 900,000 to 1.6 million. Blinken noted in a statement on Wednesday that the forcible displacement of a country’s civilian population was a “grave breach of the Fourth Geneva Convention … and is a war crime,” and called on the Kremlin to immediately return any Ukrainian civilians taken to Russia to their homes.

The secretary of state claimed that the efforts to remove Ukrainian civilians from Russian-occupied areas had attempted to “filter out” Ukrainian military and government officials, journalists, and civil society activists, and alleged that the deportations were collectively part of “an apparent effort to change the demographic makeup of parts of Ukraine.” Some Ukrainian deportees have reportedly been tortured and killed while in captivity.

Russia has reportedly engaged in similar filtration operations in other wars, including its decade-long war and counterinsurgency campaign in Chechnya from 1999 until 2009. In that conflict, as many as 200,000 Chechens passed through “filtration camps,” where they were screened for anti-Russian sentiments and frequently subjected to beatings and other abuses.

Blinken noted the similarity in his comments, adding that the United States would “support … Ukrainian and international authorities’ efforts to collect, document, and preserve evidence of atrocities.”

Trevor Filseth is a current and foreign affairs writer for the National Interest.

Image: Reuters.