Most spies and traitors were hanged at Wandsworth Prison during the war. The decision to execute Jakobs by Firing Squad at the Tower appears to be because he was still suffering from his injuries – he could not stand up. He was blindfolded and placed in a chair for the execution – the officer in charge gave a silent signal to the Firing Squad and he was shot dead.
Plans for the men to be evacuated by submarine had to be abandoned when the rendezvous site was compromised, and the plan had made no provision for an alternative rendezvous point. In any event the the escaping men, who travelled in four groups, found it extremely difficult to travel covertly across country in a landscape packed with small farms. They were all soon captured.