The Topography memorial is built around the ruins of buildings where the Gestapo secretpolice, the SS and the Reich Security Main Office ran Hitler's police state from 1933 to 1945.
Mr Zhou was party secretary at the ministry of public security from 2002-07, before becoming the Politburo's man in charge of domestic security secret police and all.
Most of the abuses were carried out by Mr Habre's dreaded secretpolice, the National Security Service or Direction de la Documentation et de la Securite (DDS).