As cities across Ukraine marked Children’s Day on Wednesday, Volodymyr Zelensky accused Russia of deporting more than 200,000 children and described the tragic fate of those killed, writes CNN.

In his nightly address, Ukraine’s president called deportations “one of Russia’s most heinous war crimes”, where people are sent to remote regions to “forget about Ukraine and not be able to return”.

“These are orphans from orphanages. Children with parents. Children separated from their families”, he said in an English translation posted on the Ukrainian government’s website.

Zelensky said that 243 children have been killed in the war, with 446 injured and 139 missing, adding that “these are only those we know about”.

He did not elaborate on the numbers, which could not be independently verified.

Zelensky named children who he said had been killed, from younger than 2 to 15, spanning Odessa to Izyum and Mariupol, including sisters Varvara and Polina from Mariupol, who he said died after Russia shelled an apartment building.

According to UNICEF, 5.2 million children need humanitarian assistance.