After the establishment of Protectorate of Bohemia and Moravia, and the legal exclusion of all Jews and people labeled as Jews from the society, Hagibor became the last spot of freedom. The only other accessible green spaces were Jewish cemeteries.
Many children spent their entire days at Hagibor, and it became necessary to create programming for them. Fredy Hirsch, a Jewish refugee from Germany, undertook this task. He was employed by the Jewish Community of Prague, and together with colleagues, he created a timetable of activities, including sporting and cultural events and illegal education, for Jewish children. At Hagibor, Hebrew was taught, the famous Brundibár opera premiered, and there were drawing and singing courses.
All this ended in the autumn of 1941 when mass deportations started. Fredy Hirsch was deported to Terezín in December; the rest of the Hagibor instructors were deported in 1942. By the end of that year, 36,825 people (including young adults and children) were deported from Prague in thirty-eight transports. Only a few survived the Holocaust.