A Ukrainian man who survived the Nazi Holocaust during World War Two has been killed during a Russian attack on the eastern city of Kharkiv.
Boris Romantschenko, 96, died during Russian shelling of his apartment block on Friday, relatives said.
Russian forces have been relentlessly shelling Kharkiv, which lies just 30 miles (50km) from the border, for over three weeks.
Romanchenko, who was born in northeastern Ukraine, was deported to Dortmund, Germany, in 1942, the organization said. After a failed escape, he was sent to four camps — Buchenwald, Peenemünde, Mittelbau and Bergen-Belsen.
More than 100,000 people combined were killed in Buchenwald and Bergen-Belsen.
"We mourn the loss of a close friend," the foundation said. "We wish his son and granddaughter, who gave us the sad news, a lot of strength in these difficult times."
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."
Mr Romantschenko's death comes more than three weeks after President Vladimir Putin sought to justify his invasion to the Russian people by telling them his goal is to"de-Nazify Ukraine".
Western leaders have condemned these claims and pointed out that Ukraine's president, Volodymyr Zelensky, is Jewish.
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.