On August 4, 1944, German and Dutch SS men led by SS Oberscharführer Josef Zilberbauer raided the hiding place. The identity of the Dutch citizen who informed on the fugitives is uncertain, but the most probable suspect (and until 2002 the only one) is Willem van Maaren, who worked in the warehouse of the building where they were hidden. On September 3, 1944 all eight of them were sent to Auschwitz on the last transport from Westerbork, which numbered about a thousand people. Edith Frank died of starvation in Auschwitz at the beginning of January 1945. Margot and Anne, who were taken to Bergen-Belsen at the end of October 1944, died there in the typhus epidemic that killed thousands of prisoners at the end of February and the beginning of March, 1945. On liberation, Otto returned to Holland to discover, after long searching, that he was the only one of the eight who had survived.
The Franks had to be careful not be caught by the Germans. They covered all the windows with thick curtains. During the day they had to be extra quiet. They whispered when they talked and went barefoot so they could walk softly. At night, when the people working in the business below went home, they could relax a bit, but they still had to be very careful.
Nazi Germany maintained concentration camps (German: Konzentrationslager, KZ or KL) throughout the territories it controlled before and during the Second World War. The first Nazi camps were erected in Germany in March 1933 immediately after Hitler became Chancellor and his Nazi Party was given control of the police by Reich Interior Minister Wilhelm Frick and Prussian Acting Interior Minister Hermann Göring. Used to hold and torture political opponents and union organizers, the camps initially held around 45,000 prisoners. In 1933–1939, before the onset of war, most prisoners consisted of German Communists, Socialists, Social Democrats, Roma, Jehovah's Witnesses, homosexuals, and persons accused of 'asocial' or socially 'deviant' behavior by the Germans.