111. On the basis of the complaints referred to, preliminary inquiry 124/2009 was opened for the crime of deprivation of personal liberty, which was assigned to the Special Unit for the Investigation of Missing and Lost Persons.107 Thisassignment was questioned by the next of kin108 to which the State responded by indicating that this assignment was governed by technical reasons and criteria of the institution.109 112. As appearing in the case file, a series of steps were taken in this preliminary inquiry.110 113. In particular, on February 12 and 13, 2010, statements were taken from María de Jesús Alvarado and Juana Bustamante, who reported the phone call allegedly from Nitza Paola Alvarado Espinoza on February 3, 2010 calling for help.111 On the basis of the statements taken, the State reported, without specifying the dates the steps being reported were carried out, that officials of the PGJE requested the company TELMEX to provide them with the list of calls received by phone number 6366980101 on February 3, 2010, which request was complied with by said company.112 This report confirmed the data provided by Mrs. Juana Bustamante, regarding the phone number and the time at which the call was received. According to what the State said, on the basis of the inquiry made on the COFETEL page, it was determined that the phone number from which the call was received belonged to the company called Pegaso, to which a letter was sent requesting information about the owner of the phone line. The State indicated that it was not possible to provide the information requested because the line was purchased on the basis of a prepaid rate plan.113 The pattern of behavior of the phone line was also requested to establish related phone lines in order to secure [… continuation] to the brief of observations on the merits by the petitioners, received on November 3, 2014); Annex I. Case file. Volume XVI. Complaint filed by María de Jesús Alvarado Espinoza with the Attorney General's Office for Justice of Buenaventura on December 31, 2009, page 45 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014). 107 Annex XX. IACHR document requesting provisional measures. Annex 6 - Case file 124/2009, Official Letter No. 384/2009. 108 Annex XX. Brief of the State sent as part of the MP 10-10 proceedings with the I/A Court H.R. on February 21, 2011. Annex Minutes of the Working Meeting on Provisional Measures for the Alvarado Case, February 18, 2011. 109 Annex XX. Brief by the State sent as part of the MP 10-10 proceedings with the I/A Court H.R. on February 21, 2011. Annex Minutes of the Working Meeting on Provisional Measures in the Alvarado Case on February 18, 2011. 110 Brief of the State sent as part of the MP 10-10 proceedings with the I/A Court H.R. on May 21, 2010. In particular, with respect to the record certifying termination of the preliminary inquiry, the following two steps appear: a) on December 31, 2009, the Assistant Official of the Public Ministry of San Buenaventura Chihuahua requested Special Coordinator “B” of the Ministerial Police f the State Investigation Agency to undertake relevant investigations to clarify the facts that constitute the crime perpetrated to the detriment of the alleged victims; b) the Police Force alerted the Specialized Unit on Probably Criminal Matters about the incidents that had occurred; c) interview that Special Agent B had with Jaime Alvarado Herrera on December 31, 2009; d) Official letter to the phone company for the purpose of requesting data referring to the owner of a phone line; e) interviews that Ministerial Police Agent B had with Karla Castro Castro, Arnoldo Gutiérrez Villareal, and Mario Castro García; f) informative report regarding the results obtained from a tracking exercise carried out in various places of the locality called Ejido Benito Juárez of the Municipality of San Buenaventura; g) minutes of May 19, 2011 indicating the onsite inspection and ministerial affidavit that were carried out in Ejido Benito Juárez. Annex I. Case file. Volume XVI. Statement where it is reported that jurisdiction for preliminary inquiry was declined 124/2009, May 28, 2012, page 516 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014). 111 Annex XX. IACHR document requesting provisional measures. Annex 6 - Case file 124/2009, Complaint filed by Juana Bustamante on February 13, 2010 with the PGJE; and Annex XX. IACHR document requesting provisional measures. Annex 6 - Case file 124/2009, Complaint filed by María de Jesús Alvarado on February 12, 2010 with the PGJE; Annex I. Case file. Volume XVI. Witness statement made to the Attorney General's Office of Justice of Chihuahua on February 12, 2010, page 79 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014); Annex I. Case file. Volume XVI. Witness statement made to the Attorney General's Office of Justice of Chihuahua on February 13, 2010, page 79 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014). 112 Annex I. Case file. Volume XVI. Response from the company Teléfonos de México to official letter 424/2010 of February 9, 2010, page 72 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014). 113 Annex XX. Brief of the State sent as part of the MP 10-10 proceedings with the I/A Court H.R. on May 21, 2010. This matches what was stated by the company Pegaso Comunicaciones in response to official letter 1123/2010. See Annex I. Case file. Volume XVI. Response from the company Pegaso Telecomunicaciones to official letter 1123/2010 of January 5, 2011, page 428 of the pdf file (Annex to the brief of observations on the merits by the petitioners, received on November 3, 2014).