Chapter 16. Genocide, crimes against humanity and war crimes
Section 103. War crimes against persons
Any person is liable to punishment for a war crime who in connection with an armed conflict
(k) wounds a combatant who has surrendered or has been placed hors de combat,
Killing or wounding a combatant who has laid down his arms and surrendered at discretion - IAC
Killing or wounding a combatant who no longer has means of defence and has surrendered at discretion - IAC
EDIT.