Harmatz’s death was confirmed on Monday by his son, Ronel, according to The Associated Press. Harmatz was 91 and as of last month was living in Tel Aviv.
He was a leader of the Jewish “Avengers,” or “HaNokmim” in Hebrew, a group of approximately 50 Holocaust survivors founded by the Israeli poet Abba Kovner in order to take revenge on Germans for World War II.
Harmatz, who was born in Lithuania, was one of the last surviving group members who poisoned Nazi SS officers in an American prisoner of war camp in 1946. Over 2,200 Nazis fell sick, but no one is known to have died from the poisoning.
When Harmatz proposed to Jewish leaders in prestate Israel a plan to kill as many Germans as Jews who died in the Holocaust, figures like David Ben-Gurion were said to be appalled.
“We didn’t understand why it shouldn’t be paid back,” he told the AP last month about the group’s motivation.
Harmatz, who lost most of his family in the Holocaust, added that his goal had been to kill “as many [Germans] as possible.”
After World War II, Harmatz immigrated to Israel, where he worked for the Jewish Agency for Israel and served as director general of World ORT, the network of Jewish-sponsored vocational institutions.