With its headquarters located in Kaunas, Einsatzkommando 3a, the unit responsible for the murder of the Jews in Lithuania, was composed mainly of Gestapo, policemen and SD men. Karl Jaeger commanded Einsatzkommando 3a; the Deputy Commander was Gustav Grauer; and Joachim Hammann was third in command. The unit served as the nucleus of the KdS (Security Police Headquarters and the SD) in Lithuania, which was accountable to the Ostland Reichskommissariat.