Of the hundreds of testimonies he heard from survivors of the Nazi death camp at Auschwitz, retired German prosecutor Gerhard Wiese says the one that touched him most was of a Jewish father who had tried but failed to save his twins from the gas chamber.
The father had offered his children to Josef Mengele, the Nazi officer known as the Angel of Death for his inhumane genetic experiments focused on twins, hoping they stood a better chance of survival.
But Mengele waved them away to the gas chamber, said Wiese, the last surviving prosecutor of the Auschwitz trials which took place in Frankfurt in the 1960s of hundreds of ex-members of Adolf Hitler's feared SS group for their roles in the Holocaust.
"After this witness statement there was absolute silence in the room," said 91-year-old Wiese, as Germany and the world mark the 75th anniversary of the liberation of Auschwitz. "One wave of the hand - that's all it took for a fate to be sealed."
More than 1.1 million people, most of them Jews, perished at Auschwitz, the death camp set up by Nazi Germany in occupied Poland in 1940 to carry out Hitler's "Final Solution" to exterminate European Jews.
World leaders were due to join Holocaust survivors at Auschwitz later on Monday to mark the 75th anniversary of the liberation of the camp by Soviet troops.
Wiese is alarmed by a rising trend among Germans to distance themselves from Nazi crimes.
"Even if some people don't like it, you have to keep reminding them: 'you were born in this country and you have to live with its history: the good and the bad parts'," he said.
The German government is alarmed by rising anti-Semitism and hate crime. Last year, an anti-Semitic gunman killed two people near a synagogue in the eastern city of Halle and a far-right sympathiser was arrested on suspicion of killing a pro-immigration politician.
"CULT OF GUILT"
Mainstream parties accuse the anti-immigrant Alternative for Germany (AfD) party of contributing to an atmosphere of hate that encourages political violence. AfD leaders have also been accused of downplaying Nazi crimes.
On Monday, an AfD lawmaker was condemned for saying that Germany should put an end to its "cult of guilt" over the Holocaust.
Stefan Raepple, an AfD lawmaker in the southern state of Baden Wuerttemberg, took issue with German President Frank-Walter Steinmeier's decision to deliver a speech at Yad Vashem Holocaust Memorial in Jerusalem last week in English, not in German, to avoid using the "language of the perpetrator".