On Himmler's instructions, Heydrich formed the Einsatzgruppen (task forces) to travel in the wake of the German armies at the start of World War II. On 21 September 1939, Heydrich sent out a teleprinter message on the "Jewish question in the occupied territory" to the chiefs of all Einsatzgruppen with instructions to round up Jewish people for placement into ghettos, called for the formation of Judenräte (Jewish councils), ordered a census, and promoted Aryanization plans for Jewish-owned businesses and farms, among other measures. The Einsatzgruppen units followed the army into Poland to implement the plans. Later, in the Soviet Union, they were charged with rounding up and murdering Jews via firing squad and gas vans. Historian Raul Hilberg estimates that between 1941 and 1945 the Einsatzgruppen and related auxiliary troops murdered more than two million people, including 1.3 million Jews. Heydrich ensured the safety of certain athletes, such as Paul Sommer, a Jewish German champion fencer he knew from his pre-SS days, and the Polish Olympic fencing team that competed at the 1936 Summer Olympics.
