About 20,000 Poles were killed in the first phase of Operation Tannenberg, which involved the shooting and gassing of hospitalpatients and disabled people as part of the operation Aktion T4.
The second phase of Operation Tannenberg saw the mass murder of 36,000–42,000 in Pomerania by the end of 1939 under the codenameIntelligenzaktion ("Actions against the Intelligentsia"). The victims included children, doctors, priestsetc. The Intelligenzaktion is estimated to have ultimately killed 100,000 Poles.
Polish teachers from Bydgoszcz guarded by members of Volksdeutscher Selbstschutz before execution.In occupied Poland, on September 9, 1939, the Germans publicly executed twenty-five prominent citizens, before the Municipal Museum, in the Market Square of Bydgoszcz, as part of the mass shootings of Polishintelligentsia. To terrorise the townsfolk, the Germans displayed the bodies for six hours.Germans murdered Polish civilians in Leszno, Poland dated October 21, 1939.Intelligenzaktion in the Reichsgau Danzig-West Prussia (1939-1940).
The mass murder of hospital patients was led by the SS commander Herbert Lange, who was later appointed as Chełmno extermination camp's commandment. By mid-1940, Lange was responsible for the death of at least 1,100 patients in Owińska, 2,750 patients at Kościan, 1,558 patients at Działdowo, and hundreds of Poles at Fort VII where the mobilegas chamber (Einsatzwagen) was made along with the first gassing bunker.
Meier, Anna (2008). Die Intelligenzaktion. Die Vernichtung der polnischen Oberschicht im Gau Danzig-Westpreußen. VDM Verlag Dr. Müller. ISBN978-36-3904-721-9.
Maria Wardzyńska, "Intelligenzaktion" na Warmii, Mazurach oraz Północnym Mazowszu. Główna Komisja Ścigania Zbrodni Przeciwko Narodowi Polskiemu. Biuletyn Instytutu Pamięci Narodowej nr. 12/1, 2003/2004, ss. 38-42. ceeol.com
Wardzyńska, Maria (2009). Był rok 1939. Operacja niemieckiej policji bezpieczeństwa w Polsce. Intelligenzaktion[The Year was 1939: Operation of German Security Police in Poland. Intelligenzaktion](PDF) (in Polish). Instytut Pamięci Narodowej (Institute of National Remembrance). ISBN978-83-7629-063-8. Archived from the original(PDF file) on 29 November 2014. Retrieved 16 November 2014. Oblicza się, że akcja „Inteligencja" pochłonęła ponad 100 tys. ofiar. Translation: It is estimated that Intelligenzaktion took the lives of 100,000 Poles.
↑Brewing, Daniel (2022). In the Shadow of Auschwitz German Massacres against Polish Civilians, 1939–1945. Berghahn Book. pp.141–142. ISBN9781800730892.
↑Stanisław Dąbrowa-Kostka, Hitlerowskie afisze śmierci (eng. "Nazi death posters"), KAW Warszawa 1983, p.339, (Polish),(German),(English)
↑Piotr Semków, IPN Gdańsk (September 2006). "Kolebka (Cradle)"(PDF). IPN Bulletin No. 8–9 (67–68), 152 Pages. Warsaw, Poland: Instytut Pamięci Narodowej (Institute of National Remembrance). 42–50 (44–51/152 in PDF). ISSN1641-9561. Archived from the original(PDF) on 17 September 2018. Retrieved 8 November 2015– via direct download: 3.44 MB.
↑Janusz Kutta, "Rola Kościoła katolickiego w dziejach Bydgoszczy" (The Role of the Catholic Church in the History of Bydgoszcz), Kronika Bydgoska, vol.19, ed. W.Jastrzębski, et al., Bydgoszcz, Towarzystwo Miłośników miasta Bydgoszczy, 1998, p.14. ISSN 0454-5451.
↑Polish: Intelligenzaktion w Okręgu Rzeszy Gdańsk - Prusy Zachodnie (1939-1940).
12Artur Hojan; Cameron Munro (2015). "Nazi Euthanasia Programme in Occupied Poland 1939-1945". Overview of the liquidation of the mentally ill during actions on the Polish territory (1939-1945). The Tiergartenstrasse 4 Association, international centre for the documentation, study and interpretation of Nazi crimes. Nazi Euthanasia in European Perspective conference, Berlin, Kleisthaus, Feb. 28-30, 2013. Retrieved 2 July 2015.
1234Holocaust Research Project.org (2007). "Lange, Herbert; SS-Hauptsturmführer". Chelmno Death Camp Dramatis Personae. Holocaust Education & Archive Research Team. Retrieved 2013-05-13.