Соответствующая норма
Practice Relating to Rule 146. Reprisals against Protected Persons
Section A. Captured combatants and prisoners of war
Belgium’s Law of War Manual (1983), citing several examples of jurisprudence, states:
The persons protected by the Geneva Conventions (… prisoners of war …) … may not be made the object of reprisals. Therefore, [reprisals] may be directed only against combatants, non-protected property and a restricted group of non-protected civilians. 
Belgium, Droit Pénal et Disciplinaire Militaire et Droit de la Guerre, Deuxième Partie, Droit de la Guerre, Ecole Royale Militaire, par J. Maes, Chargé de cours, Avocat-général près la Cour Militaire, D/1983/1187/029, 1983, p. 36.