A 94-year-old former SS sergeant who served as a guard at Auschwitz has been found guilty of more than 170,000 counts of accessory to murder for helping kill 1.1 million Jews and others at the Nazi death camp.

The Detmold state court sentenced Reinhold Hanning to five years in prison, though he will remain free while any appeals are heard.

Hanning showed no reaction as the judge, Anke Grudda, read her justification for the verdict and sentence.

"You were in Auschwitz for two and a half years, performed an important function. ... You were part of a criminal organization and took part in criminal activity in Auschwitz," she said.

Several elderly Auschwitz survivors testified at the trial about their own experiences, and were among 58 survivors or their families who joined the process as co-plaintiffs as allowed under German law.

"It is a just verdict, but he should say more, tell the truth for the young people," said Leon Schwarzbaum, a 95-year-old Auschwitz survivor from Berlin.