25 This international responsibility may arise also from the acts of individuals, which, in principle, are not attributable to the State. [The obligations erga omnes to respect and ensure respect for the norms of protection, which are the responsibility of the States Parties to the Convention,] extend their effects beyond the relationship between State agents and the persons subject to its jurisdiction, since they are also manifest in the positive obligation of the State to adopt the necessary measures to ensure the effective protection of human rights in relations between individuals. The attribution of responsibility to the State for the acts of individuals may occur in cases in which the State fails to comply with the obligations erga omnes contained in Articles (1) and 2 of the Convention, owing to the acts or omissions of its agents when they are in the position of guarantors.33 78. However, the Court has also recognized that a State cannot be responsible for every human rights violation committed by individuals subject to its jurisdiction. In other words, even though the legal consequences of an act or omission of an individual is a violation of the human rights of another, that violation cannot be automatically attributed to the State, but must be considered in light of the particular circumstances of the case and the way the State has carried out its obligations as guarantor. Indeed, the nature erga omnes of the State’s Convention obligations do not entail its unlimited responsibility for every act of an individual, because the obligation of the State to adopt preventive measures to protect individuals in their relationships with each other is conditioned by its awareness of a situation of real and imminent risk for a specific individual or group of individuals, and on the existence of the reasonable possibility of preventing or avoiding that danger.34 79. In this regard, the European Court of Human Rights has found that States have: 62. […] in appropriate circumstances[,] a positive obligation […] to take preventive operational measures to protect an individual or individuals whose life is at risk from the criminal acts of another individual […]. 63. [Moreover,] not every claimed risk to life can entail for the authorities a Convention requirement to take operational measures to prevent that risk from materializing. For a positive obligation to arise, it must be established that the authorities knew or ought to have known, at the time, of the existence of a real and immediate risk to the life of an identified individual or individuals from the criminal acts of a third party and that they failed to take measures within the scope of their powers which, judged reasonably, might have been expected to avoid that risk […].35 80. In this regard, the Court has previously indicated that “by contributing to the establishment of these [“self-defense”] groups, the State objectively created a dangerous situation for its inhabitants and did not adopt the necessary and sufficient measures to prevent these groups from continuing to commit acts such as those of the instant case.”36 The Court recognizes, as it has on other occasions, that even though the State has adopted certain legislative measures to prohibit, prevent and sanction the activities of the “selfdefense” or paramilitary groups, these measures did not translate into the effective deactivation of the danger that the State helped create. Consequently, while this danger subsists, it “accentuates the State’s special obligations of prevention and protection in areas 33 Cf. Case of the “Mapiripán Massacre”, supra note 21, para. 111 and Case of the Pueblo Bello Massacre, supra note 30, para. 113. 34 Cf. Case of the Pueblo Bello Massacre, supra note 30, para. 123. 35 Cf. European Court of Human Rights, Kiliç v. Turkey, Judgment of 28 March 2000, Application No. 22492/93, paras. 62 and 63; Osman v. the United Kingdom, Judgment of 28 October 1998, Reports of Judgments and Decisions 1998-VIII, paras. 115 and 116. 36 Case of the Pueblo Bello Massacre, supra note 30, para. 126, and Case of the Ituango Massacres, supra note 21, para. 134.