the invasion. They were deployed behind the front lines to murder groups of people considered, by virtue of their social status, to be capable of abetting resistance efforts against the Germans. The most widely used lie justifying indiscriminate murders by the mobile death squads was (always the same) made-up claim of purported attack on German forces. In total, about 150,000 to 200,000 Poles died during the one-month September Campaign of 1939, characterized by the indiscriminate and often deliberate targeting of civilian population by the invading forces. Over 100,000 Poles died in the Luftwaffes terror bombing operations, like those at Wieluń. Massive air raids were conducted on towns which had no military infrastructure. The town of Frampol, near Lublin, was heavily bombed on 13 September as a test subject for Luftwaffe bombing technique; chosen because of its grid street plan and an easily recognisable central town-hall. Frampol was hit by 70 tonnes of munitions, which destroyed up to 90% of buildings and killed half of its inhabitants. Columns of fleeing refugees were systematically attacked by the German fighter and dive-bomber aircraft. Amongst the Polish cities and towns bombed at the beginning of war were: Brodnica, Bydgoszcz, Chełm, Ciechanów, Częstochowa, Grodno, Grudziądz, Gdynia, Janów, Jasło, Katowice, Kielce, Kowel, Kraków, Kutno, Lublin, Lwów, Olkusz, Piotrków, Płock, Płońsk, Poznań, Puck, Radom, Radomsko, Sulejów, Warsaw, Wieluń, Wilno, and Zamość. Over 156 towns and villages were attacked by the Luftwaffe. Warsaw suffered particularly severely with a combination of aerial bombardment and artillery fire reducing large parts of the historic centre to rubble, with more than 60,000 casualties. Terror and pacification operations In the first three months of war, from the fall of 1939 until the spring of 1940, some 60,000 former government officials, military officers in reserve, landowners, clergy, and members of the Polish intelligentsia were executed region by region in the so-called Intelligenzaktion, including over 1,000 POWs. Summary executions of Poles were conducted by all German forces without exception including, Wehrmacht, Gestapo, the SS and Selbstschutz in violation of international agreements. The mass murders were a part of the secretive Operation Tannenberg, an early measure of the Generalplan Ost settler colonization. Polish Christians as well as Jews were either murdered and buried in hastily dug mass graves or sent to prisons and German concentration camps. "Whatever we find in the shape of an upper class in Poland will be liquidated," Hitler had ordered. In the