In 1943, he was arrested and sentenced to four months in prison for having failed to include the word "Israel" in his name in a letter to a Reich official (Nazi law required Jewish men to be identified as such, as they required Jewish women to identify as "Sarah".). In May 1944, he was arrested again on the same charge and deported to the concentration camp Theresienstadt, where he spent 14 months until the end of World War II in Europe, escaping death.