Led by SD, Gestapo, and Criminal Police (Kripo) officers, Einsatzgruppen included recruits from the regular police (Orpo), SD and Waffen-SS, augmented by uniformed volunteers from the local auxiliary police force.[7] When occasion demanded, German Army commanders bolstered the strength of the Einsatzgruppen with their own regular-army troops who assisted in rounding up and killing Jews of their own accord.[8]