His jacket sparkling with war medals, 96-year old David Dushman holds back the tears as he remembers the eyes of emaciated prisoners at the Nazi death camp at Auschwitz which he helped liberate 75 years ago this month.
A Russian Jew, Dushman is one of the last surviving soldiers to have taken part in the liberation of the camp in January 1945 and he still struggles to explain how such a catastrophe could happen.
Dushman, who later became an Olympic fencer, joined the Red Army in 1941 after Nazi Germany's invasion of the Soviet Union.
"When we arrived we saw the fence and these unfortunate people, we broke through the fence with our tanks. We gave food to the prisoners and continued," Dushman told Reuters.
"They were standing there, all of them in (prisoner) uniforms, only eyes, only eyes, very narrow - that was very terrible, very terrible," Dushman recalled.
"We had not known that Auschwitz existed," said Dushman, speaking in his flat in Munich, southern Germany, where he has lived since 1996.
More than 1.1 million men, women and children lost their lives at Auschwitz, built by the Nazis in occupied Poland as the largest of their concentration camps and extermination centres.
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Some six million Jews were killed in the Holocaust.
Asked why Auschwitz happened, Dushman is flummoxed.
"I'm not a politician, it's hard for me to say. Of course it's completely incomprehensible," he said, adding he hoped nothing like it would ever happen again.
Soon after arriving at Auschwitz, Dushman was ordered to leave and push on toward Berlin.
One of just 69 men in his 12,000-strong column of tanks to survive World War Two, Dushman was seriously wounded and he had to have part of one lung removed. That did not stop him becoming a professional fencer.
"I couldn't walk at all because I got out of breath. I started _ I made up my own workout routine for one minute per day. So very, very gradually, slowly, slowly I reached a point where in 1951 I became the champion of Russia (in fencing)."
Dushman may have forged a new life but the scenes he witnessed during the war are still with him. He used to meet old comrades in Moscow every year but these days no one is left.
"I receive congratulations from (Russian President Vladimir) Putin every year on Victory Day. May 9 is the (anniversary of the) end of the Second World War," he said, looking with pride at the special letter.