From the start of the invasion of the Soviet Union in June 1941, "Einsatzgruppen" (task forces) followed the army into conquered areas and rounded up and killed Jews, Comintern officials, and ranking members of the Communist Party. Eichmann was one of the officials who received regular detailed reports of their activities. On 31 July, Göring gave Heydrich written authorisation to prepare and submit a plan for a "total solution of the Jewish question" in all territories under German control and to co-ordinate the participation of all involved government organisations. The "Generalplan Ost" (General Plan for the East) called for deporting the population of occupied Eastern Europe and the Soviet Union to Siberia, for use as slave labour or to be murdered.