General der Nachrichtentruppe Erich Fellgiebel

General der Nachrichtentruppe Erich Fellgiebel (4 October 1886 - 4 September 1944) began his military career in September 1905 as a cadet in a signal battalion. After the First World War, he was transferred to Berlin as a General Staff officer. In 1938 he became head of the army signal corps and head of armed forces communications in Armed Forces High Command. His former superior Colonel-General Ludwig Beck and Beck's successor Colonel-General Franz Halder brought Fellgiebel into contact with the military resistance circles. He was a key figure in the preparations for Operation "Valkyrie." Adolf Hitler did not fully trust Fellgiebel; Hitler considered him too independent-minded, but Hitler needed Fellgiebel's expertise. Fellgiebel was one of the first to understand that the German military should adopt and use the Enigma encryption machine. As head of Hitler's signal services, Fellgiebel knew every military secret, including Wernher von Braun's rocketry work at the Peenemünde Army Research Center. On July 20, 1944, Fellgiebel was in the "Wolf's Lair," Hitler's headquarters in East Prussia, where he attempted to cut off all communications with this center of power. Yet once it was clear that Hitler had survived the assassination attempt, Fellgiebel was forced to countermand previous orders and reestablish communications. Fellgiebel's most famous act that day was his telephone report to his co-conspirator General Fritz Thiele at the Bendlerblock, after he was informed that Hitler was still alive: "Etwas Furchtbares ist passiert! Der Führer lebt!" ("Something awful has happened! The Führer lives!"). Fellgiebel was arrested immediately at Wolf's Lair and tortured for three weeks, but did not reveal any names of his co-conspirators. He was charged before the Volksgerichtshof ("People's Court"). On 10 August 1944, he was found guilty by Roland Freisler and sentenced to death. He was executed on 4 September 1944 at Plötzensee Prison in Berlin.

Source :
https://en.wikipedia.org/wiki/Erich_Fellgiebel
http://e-wiki.org/tr/images/Plot_to_Assassinate_Hitler_1944
https://www.gdw-berlin.de/en/recess/biographies/index_of_persons/biographie/view-bio/erich-fellgiebel/?no_cache=1