Among the victims of Russia's war in Ukraine is a Holocaust survivor who devoted his life to preserving its history.

Boris Romantschenko survived four concentration camps including Buchenwald, Dora and Bergen Belsen. The 96-year-old was killed last week when Russian forces shelled his apartment building in Kharkiv, the Buchenwald and Mittelbau-Dora Memorials Foundation said in a tweet.

"Now he has been killed by a bullet that hit his house," they wrote. "We are stunned."

Citing Romantschenko's granddaughter, the group said he lived in a multistory building that was hit by Russian shelling on Friday.

It also said, according to an English translation, that he "campaigned intensively for the memory of the Nazi crimes and was vice president of the Buchenwald-Dora International Committee."

The foundation shared a photo of several men standing in a row in front of various countries' flags, with one man reading from a piece of paper.

It said that the picture was taken during a 2012 commemoration event marking the anniversary of Buchenwald's liberation and that Romanchenko was reading out the Oath of Buchenwald, which was written for the first memorial service for the dead at the camp after it was liberated in 1945, to "build a new world of peace and freedom."

Although the exact death toll of Russia's aggression in Kharkiv — Ukraine's second-largest city — is not clear, police there said at least 250 civilians have died.

Russian President Vladimir Putin has repeatedly described a goal of his military operation as the "denazification" of Ukraine, a claim that scholars have told NPR distorts both history and reality.

Earlier this month, Russian strikes in Kyiv hit the Babyn Yar Holocaust Memorial Center, where Nazis killed nearly 34,000 Jewish people over a 36-hour period in September 1941.

Ukrainian President Volodymyr Zelenskyy, who is Jewish, said in a tweet at the time that it was "history repeating."

"To the world: What is the point of saying never again for 80 years, if the world stays silent when a bomb drops on the same site of Babyn Yar?" he wrote.

This story originally appeared in the Morning Edition live blog.

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