The Catholic Austrian resistance group around the priest Heinrich Maier was formed in 1940 and then very successfully passed on plans and production facilities for V-1, V-2 rockets, Tiger tanks, Messerschmitt Bf 109, Messerschmitt Me 163 Komet and other aircraft to the Allies. This enabled them to target German production facilities. Maier advocated the following principle: "Every bomb that falls on armaments factories shortens the war and spares the civilian population." These contributions by the resistance group were also crucial for the Operation Crossbow and Operation Hydra, both missions for Operation Overlord. The very well networked group around Maier planned a revival of Austria after the war, distributed anti-Nazi leaflets and was in contact with the American secret service. In contrast to many other German resistance groups, the Maier group provided information very early on about the mass murder of Jews through their contacts with the Semperit factory near Auschwitz. In its political plans for the future shape of Austria, the group was non-partisan and had contacts with all parties of the pre-war period. The resistance group then came into the focus of the Abwehr and Gestapo through a double agent, was discovered and most of its members were executed.