Josef Jakobs SW3, on 4–5 August 1941. The trial was held "in camera" because the German agent had been apprehended in a highly classified intelligence operation known as the Double Cross System. The British were aware that Jakobs was coming because his arrival information had been passed on to MI5 by the Welsh nationalist and "Abwehr" double agent Arthur Owens. After a two-day trial which involved hearing the testimony of eight witnesses, Jakobs was found guilty of spying and sentenced to death. Jakobs's execution took place at the miniature rifle range in the grounds of the Tower of London on 15 August
Duquesne Spy Ring triangles". A German native, Paul Scholz went to the United States in 1926 but never attained citizenship. He had been employed in German book stores in New York City, where he disseminated Nazi propaganda. Scholz had arranged for Josef Klein to construct the radio set used by Felix Jahnke and Axel Wheeler-Hill. At the time of his arrest, Scholz had just given Gustav Wilhelm Kaercher a list of radio call letters and frequencies. He also encouraged members of this spy ring to secure data for Germany and arranged contacts between various German agents. Upon conviction, Scholz was sentenced to 16