Three suspected Nazi-era concentration camp guards were arrested in Germany during police raids in several states, authorities said on Thursday.
Prosecutors in Stuttgart accuse the men of having worked as SS guards at Auschwitz, the largest of the so-called death camps in occupied Poland. Nazi-era documents were seized from their homes.
One of the suspects confirmed he had been at Auschwitz but denied involvement in the killing of inmates, prosecutors said.
The three, aged 88 to 94, were taken into custody during a search of houses belonging to six men in the south-western state of Baden-Wuerttemberg on Wednesday.
They are being held at a prison hospital in Stuttgart, prosecutors said.
Raids also took place in Hesse and North Rhine-Westphalia. Prosecutors said the residences of 11 people suspected of having assisted in exterminations at Auschwitz were targeted.
Germany's central office for investigating Nazi crimes recently reviewed several cases for prosecution.
In North Rhine-Westphalia, another man confessed to having been at Auschwitz in 1942, but denied direct involvement in mass murder, prosecutors said.
In the state of Hesse, two suspected former guards of Auschwitz-Birkenau are being investigated, said senior prosecutor Doris Moeller-Scheu.
Nazi hunter Efraim Zuroff, of the Simon Wiesenthal Center in Jerusalem, welcomed the arrest of the three men. Their advanced age should not prevent authorities from prosecuting them, he said.
"They don't deserve pity," Zuroff said. "They didn't have mercy with the victims, who were often older than they are now."
Many Nazi-era crimes went unpunished after a federal court ruling in 1969 that proof of individual guilt is required.
That precedent changed in 2011, when a Munich court convicted a former Sobibor concentration camp guard John Demjanjuk of aiding and abetting the murder of more than 28,000 people.
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