Heeresgruppe C
On Sunday 29 April, Colonel Bogislaw von Bonin, who had been imprisoned for disobeying Hitler by authorising Army Group A to retreat from Warsaw in January 1945, approached the local Wehrmacht liaison office in Niederdorf and asked them to contact his old friend, Colonel General Heinrich von Vietinghoff, the commander of Army Group C with headquarters in Bolzano, Italy, on the phone. He wasn't available but von Bonin was able to speak to another friend, General Hans Röttiger, Vietinghoff's Chief of Staff, and explain the highly dangerous situation and the need for assistance.