Nebe rose through the ranks of the Prussian police force to become head of Nazi Germany's Criminal Police ("Kriminalpolizei"; Kripo) in 1936, which was amalgamated into the Reich Security Main Office (RSHA) in 1939. Prior to the 1941 German invasion of the Soviet Union, Nebe volunteered to serve as the commanding officer of "Einsatzgruppe B", one of the four death squads of the SS. The unit was deployed in the Army Group Centre Rear Area, in modern-day Belarus, and reported over 45,000 victims by November 1941. In late 1941, Nebe was posted back to Berlin and resumed his career within the RSHA. Nebe commanded the Kripo until he was denounced and executed after the failed attempt to kill Adolf Hitler in July 1944.