An 89-year-old Philadelphia man who previously admitted to being a guard at the Nazi death camp at Auschwitz was detained Tuesday by U.S. authorities on a German arrest warrant, the Associated Press reported Wednesday.

Johann “Hans” Breyer, a retired toolmaker, is accused by German prosecutors in the town of Weiden of aiding and abetting the murders of 216,000 Jews during the Holocaust at the Auschwitz-Birkenau death camp. While Breyer conceded that he was a guard at the camp in German-occupied Poland, he claimed he wasn’t responsible for any of the deaths because he worked on the perimeter.

A lawyer for Breyer contested the detention in the U.S., claiming the aged suspect is too frail. But prosecutors said an unnamed detention center will be able to accommodate Breyer, who walked with a cane during the proceedings Wednesday.

Breyer, a former Weiden resident, was under investigation by prosecutors there. Repeated U.S. attempts to revoke his citizenship were unsuccessful.

The warrant for Breyer came after the German federal prosecutors’ office found enough evidence to let Weiden continue its investigation of the 89-year-old concentration camp guard, who is the oldest person to be accused of Nazi war crimes by the United States.

According to the New York Times, Breyer was an accessory to the deaths of hundreds of thousands of Jews deported to Auschwitz from Hungary and Slovakia in 1944. Breyer allegedly worked in the Birkenau section of the Auschwitz camp, used exclusively for gas chambers and crematoria.

Efraim Zuroff, who investigates and pursues the remaining Nazi war criminals at large for the Simon Wiesenthal Center in Jerusalem, said he hoped there would be no red tape in getting Breyer extradited to Germany.

"If a country asks for him and they have a basis for the request, the United States is anxious, of course, to be rid of all of the Nazi perpetrators who immigrated there, it's a case where hopefully there will be no obstacles," Zuroff told the AP. "Germany deserves credit for doing this — for extending and expanding their efforts and, in a sense, making a final attempt to maximize the prosecution of Holocaust perpetrators."