 From 1 May 1941 to at the end of January 1943 Querner was SS and Police Leader (HSSPF) Nordsee in Military district X, based in Hamburg.Working closely with Gauleiter Karl Kaufmann Querners had responsibility over all police matters and was also involved in the deportation of the Portuguese Jewish community in Hamburg, which began at the end of October 1941.Whilst based in Hamburg Querner ordered large quantities of Zyklon-B from Tesch & Stabenow pest control company.