more than twenty years since the disappearance of Mr. Núñez, added to the acknowledgment of partial state responsibility for the violation of rights to a fair trial and to judicial protection." 103. By virtue of the foregoing, it concluded that Ecuador violated Articles 8(1) and 25(1) of the American Convention, in relation to Article 1(1) of the same instrument, as well as Article I(b) of the IACFDP, to the detriment of Fredy Núñez Naranjo and his family members. 104. The representative did not expressly refer to the alleged violations discussed in this section. 105. Regarding the alleged violation of the immediate search obligation, the State noted that, at the time when Sixto Núñez filed the complaint, the State "was already investigating the whereabouts of Mr. Fredy Núñez." On the other hand, the State did not provide specific arguments aimed at disproving the violation of Article I (b) of the IACFDP even though, in its final allegations, it withdrew the preliminary exception ratione temporis raised in the answering brief regarding such violation. B. Considerations of the Court 106. States have a legal duty to take reasonable steps to prevent human rights violations and to use the means at their disposal to carry out a serious investigation of violations committed within their jurisdictions, to identify those responsible, to impose the appropriate punishment and to ensure the victim adequate compensation.135 In particular, when it comes to investigating violations against individuals who were under state custody, the relevant authorities have the duty to initiate, ex officio and without delay, a serious, independent, impartial, and effective investigation, that is, with due diligence, substantiated by all available legal means and aimed at determining the truth.136 Such characteristics of the duty to investigate are even more applicable in cases of potential forced disappearance of a person.137 107. In response to this particular violation, in addition to the duty of due diligence and the duty to punish those responsible, the Court has emphasized the existence of an autonomous obligation to search for and locate the disappeared persons who have been subject to forced disappearance, derived from Articles 8(1) and 25(1) of the American Convention, Article X of the IACFDP, and the International Convention on Forced Disappearance of Persons.138 This duty has also been expanded upon by the United Nations Committee on Enforced Disappearances139 and by the 135 Cf. Case of Velásquez Rodríguez v. Honduras, supra, para. 174, and Case Members and Militants of the Patriotic Union v. Colombia,, supra, para. 264. 136 Cf. Case of Velásquez Rodríguez v. Honduras, supra, para. 177, and Case of Isaza Uribe et al. v. Colombia,, supra, para. 150. 137 Cf. Case of Ticona Estrada et al. v. Bolivia, supra, para. 80, and Case of Garzón Guzmán et al. v. Ecuador. Merits, Reparations, and Costs. Judgment of September 1, 2021. Series C No. 434, para. 69. 138 Cf. Case of Garzón Guzmán et al. v. Ecuador, supra, para. 75, and Case of Flores Bedregal et al. v. Bolivia, supra, para. 121. In that sense, the International Convention for the Protection of All Persons from Enforced Disappearance adopted by the United Nations General Assembly on December 20, 2006, in its Articles 15, 19(1), 24(2), 24(3), 25(2) and 25(3), refers to the obligation to search for and locate disappeared persons in a precise and differentiated manner with respect to criminal investigation. 139 Cf. Committee on Enforced Disappearance, Final observations on the report presented by Spain under Article 29, paragraph 1, of the Convention, UN Doc. CED/C/ESP/CO/1, December 12, 2013, para. Article 32, Committee on Enforced Disappearances, Final observations on the report presented by Burkina Faso under Article 29, paragraph 1, of the Convention, UN Doc. CED/C/BFA/CO/1, May 24, 2016, para. 40; Committee on Enforced Disappearances , Final observations on the report presented by Honduras under Article 29, paragraph 1, of the Convention, UN Doc. CED/C/HND/CO/1, of May 25, 2018, para. 30.f., and Committee on Enforced Disappearance, Final observations on the report presented by Chile under Article 29, paragraph 1, of the Convention, UN Doc. CED/C/CHL/CO/1, April 18, 2019, para. 27.a. -31-