Einsatzgruppe B, 655 troops initially, had its headquarters in Smolensk. Areas of operation were Belorussia and Smolensk district. Its first commander was SS-Obergruppenführer Arthur Nebe. He was implicated in the 1944-07-20 assassination attempt against Hitler and executed in the spring of 1945. Himmler replaced him with SS-Gruppenführer Erich Naumann and later SS-Oberführer dr. Horst Böhme and SS-Standartenführer dr. Heinz Seetzen. SS units, specially trained assassins, assigned terror tasks for the political administration in the Soviet Union and other eastern territories. The Einsatzgruppen worked behind the lines and murdered political opposition. The Einsatzgruppen murdered between 1.25-2 million Jews and tens of thousands of Soviet citizens and Soviet POWs.
The Holocaust : Roots, History, and Aftermath / D.M. Crowe. – Colorado, 2008. – p. 200
Einsatzgruppe B