Abstract: Internal security is very vital for the enhancement of sovereign and territorial integrity of any state. In this vein, any military operation is usually guided by special rules for opening fire in both international and non-international armed conflict. However, warring parties, including military operators have, at one time or the other, slightly observed and/or maximally disregarded these rules during armed hostilities. The attendant implications of this misnomer is colossally jeopardizing in nature. Against this backdrop, this study examines military operations associated with internal security and special rules for opening fire in armed conflicts. Accordingly, mechanism for enforcement of the law of armed conflicts, 1907 Hague Convention Ix concerning the bombardment by naval forces in time of war, institutional mechanism of enforcement, United Nations Convention on the prohibition of military or any other hostile use of environmental modification techniques, military mechanism of enforcement types of military operations associated with internal security during armed conflicts, types of forces available to a state for internal security operations, types of military operations relating to security operations, problems faced by the armed forces during armed conflicts, the armed forces attitude to internal security operations, special rules for opening fire and the military rules of engagement were appraised. Hence, the data for this research were collected mainly from secondary sources of recorded human documents. The research design was based on ex-post facto model of analysis. The analytical frame research was based on the theory of armed conflicts. To this effect, it is found that military operations and internal security are highly essential for the observance of special rules for opening fire in any armed conflict. In other words, any disconnect between the two factors often lead to non-observance of special rules for opening fire during armed combats. The study therefore, recommends that the military should be re-structured in such a way that knowledgeable persons are charged with commanding responsibilities during armed hostilities.