after vargas garcía was arrested, he became an informant for the mexican authorities, and confessed several aspects of the logistics structure in los zetas. he explained to the authorities that los zetas employed a project called "la expansión", which meant in the insides of the criminal underworld when several members of los zetas would go into a city and establish smuggling routes, and control or kill off opposition groups. the second phase of this process was known as "la contracción", when they would set up networks of radiocommunication in an area, organize safe houses, and call on gunmen to protect specific places.