In addition , the killers claimed Statement to have investigated Criminal_investigation passengers ' cellphones and text messages to determine Deciding if they were involved Participation with the Gulf Cartel or not , and that they were particularly worried about buses coming in from the states of Durango and Michoacán , two strongholds of the rival La Familia and the Sinaloa Cartels .

This part of the campaign Military_operation saw the Bombing Use_firearm of Guernica and Durango .