After German invasion of Poland, Selbstschutz worked together with the Einsatzgruppen to massacre Poles. Selbstschutz took part in the first action of elimination of Polish intelligentsia, the mass murders in Piaśnica, during which 12,000 to 16,000 civilians were murdered. An Intelligenzaktion[7] was a plan to eliminate all Polish intelligentsia and Poland's leadership class in the country.