Related Rule
Ecuador
Practice Relating to Rule 47. Attacks against Persons Hors de Combat
Ecuador’s Naval Manual (1989) states: “The following acts constitute war crimes: … denial of quarter (i.e., denial of the offer not to kill the defeated enemy).” 
Ecuador, Aspectos Importantes del Derecho Internacional Marítimo que Deben Tener Presente los Comandantes de los Buques, Academia de Guerra Naval, 1989, § 6.2.5(4).
Ecuador’s Naval Manual (1989) states:
Members of the armed forces incapable of participating in combat due to injury or illness may not be the object of attack.
Shipwrecked persons, whether military or civilian, may not be the object of attack.
Combatants cease to be subject to attack when they have individually laid down their arms to surrender, when they are no longer capable of resistance or when the unit in which they are serving or embarked has surrendered or has been captured. 
Ecuador, Aspectos Importantes del Derecho Internacional Marítimo que Deben Tener Presente los Comandantes de los Buques, Academia de Guerra Naval, 1989, §§ 11.4, 11.6 and 11.8; see also § 8.2.1.
The manual also states:
The following acts constitute war crimes:
3.Offences against the sick and wounded, including killing, wounding, or mistreating enemy forces disabled by sickness or wounds.
4.… offences against combatants who have laid down their arms and surrendered.
5.Offences against the survivors of ships and aircraft lost at sea, including killing, wounding, or mistreating the shipwrecked, and failing to provide for the safety of survivors as military circumstances permit. 
Ecuador, Aspectos Importantes del Derecho Internacional Marítimo que Deben Tener Presente los Comandantes de los Buques, Academia de Guerra Naval, 1989, § 6.2.5(3)–(5).