In October 18, 1942 Adolf Hitler issued an order that all Commandos captured in Europe and Africa (but excluding seamen), should be immediately killed even if they attempted to surrender. Any man or small group of men with the uniform of Commando or similar unit would be turned over to the Sicherheitsdienst (SD or Nazi security service) for summary execution. He claimed that since Commandos were ordered not to take prisoners, (which was false), they would not be taken as prisoners, either.
Arguably, any members of Resistance movements, Partisan forces, the SOE, OSS and any belligerent not carrying arms openly or wearing a fixed distinctive emblem recognisable at a distance, (per Article 1, Chapter 1, Section 1 of the Annex to the Hague Convention II, 1899), are not covered by the terms of the Laws and Customs of War on Land and are liable to be regarded as a Franc-tireur or spy.
Generals like Erwin Rommel and Albrecht Kesselring did not obey the order but relied on the Geneva conventions.
Hitler later extended this treatment to captured Allied pilots, and the SD's role was taken over by the Gestapo.
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