63 83. The need to consider integrally the offense of forced disappearance of an autonomous, continuing or permanent nature, composed of multiple elements with their complex interrelationships, and related criminal acts, can be deduced not only from the its definition in the abovementioned Article III of the Inter-American Convention on Forced Disappearance of Persons, the travaux préparatoires for this instrument,65 its preamble and provisions, but also from Article 17(1) of the 1992 United Nations Declaration on the Protection of all Persons from Forced disappearance, which even adds one further element, related to the obligation to investigate, by indicating that this must be considered “a continuing offence as long as the perpetrators continue to conceal the fate and the whereabouts of persons who have disappeared and these facts have not been clarified.” International case law also reflects this understanding,66 as do Articles 4 and 8(1)(b) of the abovementioned United Nations international convention on this matter. 84. In brief, the Court finds that, as may be deduced from the preamble to the aforesaid Inter-American Convention,67 faced with the particular gravity of such offenses and the nature of the rights harmed, the prohibition of the forced disappearance of persons and the corresponding obligation to investigate and punish those responsible has attained the status of jus cogens. 85. To sum up, the above findings on the offense of forced disappearance of persons respond to the need to prevent and protect against this type of act. Thus, although classified as violations of the right to life, humane treatment and personal liberty, the fact that this judgment deals with the specifics of the instant case as a series of factors that compose the forced disappearance of victims is in keeping with the continuing or permanent nature of this phenomenon and the need to consider the context in which the violations occurred, examine their effects over time and consider their consequences as a whole. (b) The State’s international responsibility increased because the facts occurred within the framework of “Operation Condor” and due to failure to comply with the obligation to investigate them effectively 86. As established in the section on proven facts (supra paras. 61(15) to 61(50)), the surveillance of Dr. Agustín Goiburú and his family continued after he abandoned Paraguay in 1959 and went into exile in Argentina. Several documents discovered in 65 Cf. Annual Report of the Inter-American Commission on Human Rights 1987-1988, Chapter V.II. This crime “is permanent because it is committed permanently, rather than instantaneously, and it continues while the person remains disappeared” (OEA/CP-CAJP, Report of the President of the Working Group responsible for examine the draft Inter-American Convention on Forced Disappearance of Persons, doc. OEA/Ser.G/CP/CAJP-925/93 rev.1, of January 25, 1994, p. 10). 66 Cf. European Court of Human Rights, Cyprus v. Turkey, judgment of 10 May 2001, Application No. 25781/94, paras. 136, 150 and 158; United Nations Human Rights Committee, Ivan Somers v. Hungary, Communication No. 566/1993, 57th session, CCPR/C/57/D/566/1993 (1996), July 23, 1996, para. 6.3; E. and A.K. v. Hungary, Communication No. 520/1992, 50th session, CCPR/C/50/D/520/1992 (1994), May 5 1994, para. 6.4, and Solorzano v. Venezuela, Communication No. 156/1983, 27th session, CCPR/C/27/D/156/1983, March 26, 1986, para. 5.6. 67 Considering that the forced disappearance of persons violates numerous non-derogable and essential human rights enshrined in the American Convention on Human Rights, in the American Declaration of the Rights and Duties of Man, and in the Universal Declaration of Human Rights. (InterAmerican Convention on Forced Disappearance of Persons, preamble).