"Captured combatants must be treated as Prisoners of War in accordance with the Third Geneva Convention, " it added.

CNN: Amnesty appeals to warring sides

According to the Third Geneva Convention itself (the one covering POWs), for a person to qualify as a POW and be accorded the treatment proscribed in said convention, that person must be affiliated (either regular army or militia meaning some sort of uniform) with a "High Contracting Power" (a state that was party to the convention but for argument's sake we'll say any state).

CENTERFORSECURITYPOLICY: Amnesty ignorant again