Auschwitz survivor Justin Sonder arrives at a courtroom in Detmold, Germany, Feb. 12, 2016, for the second day of the trial of Reinhold Hanning. Photo: Reuters / Bernd Thissen / Pool.

A survivor of the Auschwitz death camp who assisted a German court in convicting an SS war criminal passed away on Tuesday in Chemnitz — the eastern German city of his birth.

Justin Sonder, who died at the age of 95, was deported by the Nazis to the Auschwitz concentration camp in Poland in 1943 — when he was 17.

While Sonder and his father Leo survived, his mother Zita and eleven other members of their family were exterminated in the gas chambers.

In 2016, Sonder gave crucial evidence at the trial in Germany of Reinhold Hanning — a former SS guard who was convicted as an accessory to the murder of 170,000 Jews.

In his testimony, Sonder recalled that he had been lined up for the notorious “selektion” process — when Nazi officers decided which prisoners to send to the gas chambers and which to retain as slave labor — no less than 17 times.

“I don’t have the words to describe how it was, when you know that you could be dead in one or two hours, it made you sick, made you crazy,” Sonder told the court in a voice quivering with emotion.

In an interview with the German newspaper Bild prior to his passing, Sonder — who lived in communist-ruled East Germany after the war — said he hadn’t spoken about his experience in Auschwitz following the Holocaust. In 1990, in the wake of the collapse of the GDR, he began speaking at schools, giving lectures several times a week.

In an article commemorating Sonder on Tuesday, Bild reminded its readers of the answer he gave when asked in his original interview whether he was religiously devout. “No, because God would have prevented the murder of more than one million children,” Sonder replied.

Asked whether there was anything in the world today that he was scared of, Sonder answered in the affirmative.

“The terror and the situation in the world scares me,” Sonder stated. “We need more stability and hope for a good existence.”