Antoni Dobrowolski, a former Polish teacher arrested by the Gestapo in 1942 for teaching underground lessons to students, died on Sunday at the age of 108, according to a Polish official speaking with the Associated Press. He was the oldest known survivor of Germany's largest death camp.

Banning elementary education beyond four years was one of many tactics employed by Nazi Germany after its invasion of Poland in 1939—a strategy aimed at undermining Polish culture and wiping out its intelligentsia and leadership class. A spokesman at the Auschwitz-Birkenau state museum told the AP Dobrowolski died in the northwester town of Debno.

Apparently, he never lost his passion for teaching. According to the Polish newspaper Gazetaafter Dobrowolksi was liberated in 1945, he became head of a primary school in Debno and, a number of years later, directed a local high school. Prior to his arrest by the Germans, the newspaper says Dobrowolski was a member of the Secret Teaching Organization an underground organization formed in response to the mass closure of educational institutions and repression of teachers. In total, Germans are believed to have killed at least 1.1 million people at Auschwitz—most of the victims were Jewish but many were also Roma, non-Jewish Poles and other persecuted groups.