Chapter II
Crimes
Section II
War crimes
Article 11
War crimes involving the employment of prohibited methods of war
Anyone who, in the context of an international armed conflict or a non-international armed conflict:
(h) Treacherously kills or wounds enemy combatants;
shall be punished with a term of imprisonment of 10 to 25 years.
Killing or wounding treacherously a combatant adversary - NIAC
Killing or wounding treacherously individuals belonging to the hostile nation or army - IAC
EDIT.