Related Rule
Ecuador
Practice Relating to Rule 6. Civilians’ Loss of Protection from Attack
Ecuador’s Naval Manual (1989) states:
Civilians who take a direct part in hostilities by taking up arms or otherwise trying to kill, injure or capture enemy personnel or destroy enemy property lose their immunity and may be attacked. Similarly, civilians serving as guards, intelligence agents or lookouts on behalf of military forces may be attacked. 
Ecuador, Aspectos Importantes del Derecho Internacional Marítimo que Deben Tener Presente los Comandantes de los Buques, Academia de Guerra Naval, 1989, § 11.3.