A/HRC/45/13/Add.3 migrants.273 Any effective investigation should be undertaken with the requisite cooperation between States to conduct transnational investigations into these cases. 274 The Working Group recalled that an effective investigation of disappeared migrants comprises forensic investigative resources, the compilation of all relevant ante-mortem information, including the genetic information of the relatives and the creation of a central database. 275 Investigative steps imply the location of clandestine graves or other places where bodies may be concealed in migratory transit areas and the establishment of a register of corpses found.276 139. The Inter-American Commission on Human Rights held that the failure to take effective investigative steps and further collusion between State agents and criminal organizations led to the enforced disappearances of migrants in Mexico.277 The Office of the Prosecutor of Human Rights of Guatemala documented severe flaws in relation to effective investigations in relation to the location and identification of bodies and the burial of human remains of migrants transiting through Mexico.278 140. Positive practices by States include the collection of a total of 229 genetic markers and 348 fingerprints in 2016 in Tunisia in connection with a list of 505 persons reported missing on the Italian coast as a result of clandestine immigration since 14 January 2011. A database was also compiled from the file of missing persons and steps were taken to intensify diplomatic action. 279 In Mexico, a forensic commission mandated to exhume, identify and return the mortal remains of missing migrants was established in August 2013 for three burial sites of mass graves.280 G. Obligations to investigate disappearances committed by non-State actors 141. Enforced disappearances committed by non-State actors present particular challenges for the protection of victims and warrant investigative measures to be undertaken by the State as part of their due diligence obligations.281 Even if the State is not involved in the commission of the enforced disappearance through the collusion or acquiescence of State agents with non-State actors, the State breaches its obligation when not engaging in effective investigations.282 142. The European Court and the Inter-American Court held that the same requirements of ex officio investigations, promptness, effectiveness, involvement of family members, and impartiality of investigating entities apply in relation to enforced disappearances allegedly committed by non-State actors.283 143. The European Court stated in Tsechoyev v. Russia (paragraph 145): “The obligation to conduct an effective official investigation also arises where death occurs in suspicious circumstances not imputable to State agents. It has developed a number of guiding principles to be followed for an investigation to comply with the Convention’s 273 274 275 276 277 278 279 280 281 282 283 46 A/HRC/33/51/Add.1, para. 67; A/HRC/36/39/Add.2 para. 65. JAL GMB 1/2018. A/HRC/36/39/Add.2, para. 68. Ibid. 69. Inter-American Commission on Human Rights, OEA/Ser.L/V/II. Doc. 48/13, 30 December 2013, para. 162. Ibid, para. 170; See Fundación para la Justicia y el Estado Democrático de Derecho et al., Alternative Report to the Committee against Torture, May 2012, available at tbinternet.ohchr.org/Treaties/ CAT/Shared%20Documents/MEX/ INT_CAT_NGO_MEX_12976_S.pdf, paragraphs 136–150. See the contribution for this report by Tunisia. Available at www.ohchr.org. See Gabriella Citroni, “The first attempts in Mexico and Central America to address the phenomenon of missing and disappeared migrants,” International Review of the Red Cross No. 905 (August 2017) p. 749. IACHR, Velásquez-Rodríguez v. Honduras (see footnote 123) para. 172; See Section III, K of the Thematic Report. European Court of Human Rights, Mahmut Kaya v. Turkey (see footnote 187) paragraph 78. European Court of Human Rights, Tsechoyev v. Russia (footnote 170) paragraph 145; IACHR, The Pueblo Bello Massacre v. Colombia (see footnote 127) paras. 142–146.