61 violates the obligation to respect the rights protected by the Convention and to guarantee their free and full exercise83, of both the victim, and of his next of kin to know his whereabouts84. 130. According to the jurisprudence of this Court, forced disappearance “frequently involves secret execution [of those detained], without trial, following by concealment of the corpse in order to eliminate any material evidence of the crime and to ensure the impunity of those responsible”85. Due to the nature of the phenomenon and its probative difficulties, the Court has established that if it has been proved that the State promotes or tolerates the practice of forced disappearance of persons, and the case of a specific person can be linked to this practice, either by circumstantial or indirect evidence86, or both, or by pertinent logical inference87, then this specific disappearance may be considered to have been proven88. 131. Taking this into account, the Court attributes a high probative value to testimonial evidence in proceedings of this type, that is, in the context and circumstances of cases of forced disappearance, with all the attendant difficulties, when, owing to the very nature of the crime, proof essentially takes the form of indirect and circumstantial evidence89. 132. This Court has considered proven, on the basis of both the circumstantial evidence and the direct evidence, that, as the Commission has indicated, at the time of the facts of the case, the Army had a practice of capturing guerrillas, detaining them clandestinely without advising the competent, independent and impartial judicial authority, physically and mentally torturing them in order to obtain information and, eventually, killing them (supra 121f). It can also be asserted, according to the evidence submitted in this case, that the disappearance of Efraín Bámaca Velásquez is related to this practice (supra 121 h, i, j, k, l), and therefore the Court deems it to have been proved. 133. There is sufficient evidence to conclude that the facts indicated in relation to Efraín Bámaca Velásquez were carried out by persons who acted in their capacity as agents of the State, which involves the international responsibility of Guatemala as State Party to the Convention. 83 Cf. Paniagua Morales et al. Case, supra note 50, para. 90; Fairén Garbi and Solís Corrales Case, supra note 53, para. 152; Godínez Cruz Case, supra note 53, paras. 168-191; and Velásquez Rodríguez Case, supra note 53, paras. 159-181; 84 Cf. Blake Case, supra note 52, para. 66; Fairén Garbi and Solís Corrales Case, supra note 53, para. 147; Godínez Cruz Case, supra note 53, para. 165; and Velásquez Rodríguez Case, supra note 53, para. 158. 85 Cf. Godínez Cruz Case, supra note 53, para. 165; and Velásquez Rodríguez Case, supra note 53, para. 157. 86 Cf. Villagrán Morales et al. Case (the “Street Children” Case), supra note 52, para. 69; Castillo Petruzzi et al. Case, supra note 50, para. 62; Paniagua Morales et al. Case, supra note 50, para. 72; Blake Case, supra note 52, paras. 47 and 49; Caso Gangaram Panday. Judgment of January 21, 1994. Series C No. 16, para. 49; Fairén Garbi and Solís Corrales Case, supra note 53, paras. 130-133; Godínez Cruz Case, supra note 53, paras. 133-136; and Velásquez Rodríguez Case, supra note 53, paras. 127-130. 87 Cf. Blake Case, supra note 52, para. 49. 88 Cf. Similarly, Blake Case, supra note 52, para. 49; Godínez Cruz Case, supra note 53, paras. 127 and 130; and Velásquez Rodríguez Case, supra note 53, para. 124. 89 Cf. Blake Case, supra note 52, para. 51.