Ewald Heinrich von Kleist, a former German army lieutenant who took part in a plot to assassinate Adolf Hitler, has died at the age of 90, a think tank he co-founded said Wednesday.
Von Kleist, who was arrested after the 1944 bid to remove Hitler and sent to a concentration camp, died last Friday in the southern German city of Munich, a spokesman for the Munich Security Conference said.
Under the "20 July" plot, German army officers teamed up with members of the resistance including trade unionists to try to blow up Hitler at Rastenburg, in Eastern Prussia, now part of Poland.
Among the key plotters was Claus Schenk von Stauffenberg -- played by American Hollywood actor Tom Cruise in the 2008 film "Valkyrie" about the failed assassination --, who had personally recruited von Kleist.
Von Kleist was 22 at the time and volunteered to wear a suicide vest at a meeting with Hilter.
But the plot failed and Hitler survived although he was injured in the blast.
Leading members of the plot were arrested shortly afterwards and executed.
Von Kleist was imprisoned at the Bendlerblock building in Berlin where the plot had been hatched and today is used by the defence ministry, before he was sent to Ravensbrueck concentration camp.
After the Second World War, he studied law and economics and went into publishing.
He was also a co-founder of the Munich Security Conference, which annually brings together global defence and foreign policy chiefs.
"We lost a great German, a great security policy maker," Oliver Rolofs, spokesman for the conference told AFP.
During a 2010 commemoration of the failed plot, von Kleist said their driving motive had been "to want to end the dreadful crimes" of the Nazi regime, which continued for nearly another 10 months after the assassination attempt.