Thousands of Ukrainian children abducted by Russia amid the country’s ongoing invasion are being forcibly “reeducated” in at least 210 facilities around Russia and Russian-occupied Ukraine, according to a study published Tuesday by the Yale School of Public Health’s Humanitarian Research Lab.

The researchers say that Ukrainian children in the eastern regions occupied by Russia since its full-scale invasion began in February 2022 have been sent to the facilities where, “in many cases, (they) are placed in programs of forced militarization that include, though are not limited to, combat and paratrooper training.”

“Children at some facilities have been engaged in the production of military equipment for Russia’s armed forces, including drones,” the Yale study said.  

The researchers said their conclusions were based on “publicly available data sources and commercially available satellite imagery,” and that the analysts “evaluated each data source for reliability, veracity, and credibility using assessment criteria derived from the Berkeley Protocol” for open-source research, and an intelligence assessment framework used by NATO.

The Yale researchers do not provide an estimate of the total number of children abducted by Russia. They note that while some have been returned, “other groups of children have been held indefinitely. In some cases, children who have entered this network of camps, so-called family centers, and other facilities have entered Russia’s program of coerced fostering and adoption, eventually being placed with families in Russia and becoming naturalized citizens of the Russian Federation.”

The report details at least eight different types of facilities to which Ukrainian children have been taken, including summer camps, mental health institutions, at least one military base and even a monastery. It said the objective for Russian authorities is to indoctrinate the Ukrainian children with pro-Russian, anti-Ukrainian cultural and patriotic narratives.

Ukraine’s state-run “Bring Kids Back” program, launched by President Volodymyr Zelenskyy, says more than 19,500 Ukrainian children have been abducted since Russia’s invasion began. It says only about 1,600 have been returned, including 101 who were bought back in August.

In March 2023, the U.N.’s International Criminal Court issued an arrest warrant for Russian President Vladimir Putin, accusing him of committing “the war crime of unlawful deportation of population (children) and that of unlawful transfer of population (children) from occupied areas of Ukraine to the Russian Federation.”

The court also issued an arrest warrant for Maria Alekseyevna Lvova-Belova, the commissioner for children’s rights in the Office of the President, accusing her of committing the same crimes.

Zelenskyy said last week that he would raise the issue of abducted Ukrainian children during the U.N. General Assembly meeting in New York next week. He said he would host the event along with Canadian Prime Minister Mark Carney, and that “many leaders will join us.”

In August, after meeting with Zelenskyy and European leaders in Washington, President Trump said in a social media post that he and European Commission President Ursula von der Leyen had discussed “the massive Worldwide problem of missing children,” with a goal of “bringing them home to their families.”

Von der Leyen, in her own post, thanked Mr. Trump, and added that “every single Ukrainian child abducted by Russia must be returned to their families.” 

Mr. Trump didn’t mention Russia specifically in his own remarks. First lady Melania Trump, several days before the White House meetings, had penned an open letter to Putin pleading with the Russian leader to protect “the innocence of these children,” though not specifying which children she was referring to. 

Mr. Trump handed that letter to Putin in person when the two men met in Alaska last month, according to The Wall Street Journal.

Russia’s state-run media did not indicate any response from the Kremlin to the allegations made in the Yale lab’s report. The Russian Embassy in Washington, D.C., didn’t immediately respond to a request for comment from CBS News.

Two years ago, in a report published during the Biden administration that was titled “The Kremlin’s War Against Ukraine’s Children,” the State Department noted the ICC arrest warrants, and said Russia’s response included “threats of nuclear strikes, false claims about Western ‘experiments on children’ and anti-Russian ‘hysteria,'” as well as “calls for the arrest of ICC judges, and claims that Ukraine’s children were taken away ‘for their safety.'”

Putin’s government “appears determined to erase Ukraine’s existence as a state by attempting to rob it of its future,” the Biden-era State Department report said, adding that “mounting evidence shows Russia uses forcible relocation, re-education, and, in some cases, adoption of Ukraine’s children as key components of its systematic efforts to suppress Ukraine’s identity, history, and culture.”

CBS News has asked the State Department if it accepts the findings presented by the Yale lab, whether the Trump administration has any new plans to address the matter of abducted Ukrainian children as it continues pushing for a diplomatic resolution to the war in Ukraine, and whether the U.S. will be represented at the meeting hosted by Zelenskyy and Carney during the U.N. General Assembly next week. The State Department did not immediately respond to CBS News’ requests for comment.