CAMBODIA – PENAL CODE
BOOK 2 - CRIMES AGAINST PERSONS
TITLE 1 - GENOCIDE, CRIMES AGAINST HUMANITY, WAR CRIMES
CHAPTER 3 - WAR CRIMES
Article 194: Other war crimes
Any of the following acts also constitutes a war crime if it is committed during an international or non-international armed conflict:
(1) employing poisonous weapons or other weapons calculated to cause unnecessary suffering:
Employing poison or poisoned weapons - IAC
Employing weapons, projectiles and materials and methods of warfare which cause superfluous injury or unnecessary suffering - IAC
EDIT.