The World Jewish Congress (WJC) on Tuesday praised German authorities for their crackdown on former Nazi war criminals.
Germany arrested several such people this week, one of whom is a 93-year-old former Nazi medic who served at the Auschwitz death camp.
Prosecutors quoted by AFP said Tuesday that the unnamed man was arrested on multiple charges of aiding and abetting murder.
The 93-year-old, who was arrested at his home near Neubrandenburg north of Berlin, underwent a medical checkup before he faced a judge and was then taken into pre-trial detention, reported AFP.
The former SS member allegedly assisted in the mass murder of prisoners who arrived on eight transports from Germany, Austria, France, Italy, the Netherlands and Slovenia in September 1944.
Of the arrivals, 1,721 were killed in gas chambers after they were deemed unfit for forced labor at the Auschwitz-Birkenau camp, prosecutors said.
WJC president Ronald Lauder praised German authorities for "not relenting in the pursuit of those who murdered, or aided in murdering, thousands of people during World War II."
"The prosecution of those who participated in terrible crimes sends a clear message that justice must be done, no matter how late the hour," he said in a statement quoted by AFP.
The pensioner's arrest followed a tip-off from the German office investigating Nazi war crimes with a recommendation to bring charges but prosecutors did not specify when it took place.
"There cannot be a statute of limitation for crimes against humanity, and mass murderers must continue to live in fear of the long arm of the law," Lauder said.
The series of arrests comes following the 2011 Munich trial of John Demjanjuk, a Nazi war criminal charged of assisting in the murder of 28,060 people at the Sobibor death camp and sentenced to five years. The former Nazi died in 2012.
The trial changed limitations by which Germany only prosecuted Nazi war criminals if witness testimony showed they personally committed atrocities. Thanks to the Demjanjuk ruling, all former camp guards can be tried for their part in the Nazi genocidal mass murder.
Some of the arrests have, unfortunately, come too late. Several weeks ago, a German court ruled that Hans Lipschis, a 94-year-old man deported from the United States for lying about his Nazi past is unfit for trial on allegations that he was an accessory to thousands of murders as an SS guard at Auschwitz.
The Ellwangen state court said Lipschis is suffering from "worsening dementia" and couldn't be tried.
Lipschis is one of 30 suspected former Auschwitz guards against whom a special German prosecutors' office in September said it had collected enough evidence to warrant charges.
Efraim Zuroff, head of the Simon Wiesenthal Center in Jerusalem, said he hoped the Lipschis decision would be a "wakeup call" for other prosecutors to prioritize the new Auschwitz cases.