Related Rule
Colombia
Practice Relating to Rule 106. Conditions for Prisoner-of-War Status
Section A. Distinction from the civilian population
Colombia’s Instructors’ Manual (1999) states:
Combatants must distinguish themselves from the civilian population when they participate in combat action or in an operation preparatory thereto. Members of regular Armed Forces normally wear their uniform. Members of other militias, such as rebels and guerrillas, use a distinctive sign and normally carry their arms openly. 
Colombia, Derechos Humanos & Derecho Internacional Humanitario – Manual de Instrucción de la Guía de Conducta para el Soldado e Infante de Marina, Ministerio de Defensa Nacional, Oficina de Derechos Humanos, Fuerzas Militares de Colombia, Santafé de Bogotá, 1999, p. 16.