 Complete the following phrase:  During World War II, the Nazi German were a sub-group of the  mobile killing squads  up to 3,000 men total  usually composed of 5001,000 functionaries of the SS and Gestapo, whose mission was to exterminate Jews, Polish intellectuals, Romani, and communists in the captured territories often far behind the advancing German front. Einsatzkommandos, along with Sonderkommandos, were responsible for the systematic killing of Jews during the aftermath of 