Johann Breyer, a former Nazi guard at the Auschwitz concentration camp, died on July 22, only hours before a U.S. magistrate judge agreed to have Breyer extradited to Germany.
The 89-year-old died at Thomas Jefferson University Hospital, U.S. Marshals Service spokesman Jim Burke told the Daily News.
Before learning of Breyer’s death, U.S. Magistrate Judge Timothy Rice issued a 31-page order for his extradition to Germany, where he would have been tried for war crimes.
"Germany has established probable cause of Breyer's complicity in the mass murders at Auschwitz," Rice wrote. "As outlined by Germany, a death-camp guard such as Breyer could not have served at Auschwitz during the peak of the Nazi reign of terror in 1944 without knowing that hundreds of thousands of human beings were being brutally slaughtered in gas chambers and then burned on site."
Federal authorities arrested  the retired toolmaker at his home in Northeast Philadelphia last month.
The German government had been seeking his extradition after charging him with 158 counts of complicity in the commission of murder; each count representing a trainload of Jews who were taken to be killed at Auschwitz.
Breyer’s age and the passage of time since World War II had sparked some debate  about the relevancy of trying former Nazis.
In the past Breyer had admitted to serving as a guard at Auschwitz, where 1.1 million men, women and children had been murdered, but said he had no direct responsibility for the killing of Jews.