After the invasion of the Soviet Union on 22 June 1941, the Einsatzgruppen's main assignment was to kill civilians, as in Poland, but this time its targets specifically included Soviet Communist Party commissars and Jews.[43] In a letter dated 2 July 1941 Heydrich communicated to his SS and Police Leaders that the Einsatzgruppen were to execute all senior and middle ranking Comintern officials; all senior and middle ranking members of the central, provincial, and district committees of the Communist Party; extremist and radical Communist Party members; people's commissars; and Jews in party and government posts. Open-ended instructions were given to execute "other radical elements (saboteurs, propagandists, snipers, assassins, agitators, etc.)."