Los Metros
Los Metros is a faction of a Mexican drug trafficking organization known as the Gulf Cartel. The group was formed in the late 1980s during the reign of Osiel Cárdenas Guillén, the former leader of the cartel, to provide security to the organization's leaders as the cartel's armed wing. The leader of Los Metros, Mario Ramirez Treviño, alias X-20, was arrested on 17 August 2013. Fight with Los Rojos In the late 1990s, Osiel Cárdenas Guillén, the former leader of the Gulf cartel, had other similar groups besides Los Zetas established in several cities in Tamaulipas. Each of these groups were identified by their radio codes: the Rojos were based in Reynosa; the Metros were headquartered in Matamoros; and the Lobos were established in Laredo. The infighting between the Metros and the Rojos of the Gulf cartel began in 2010, when Juan Mejía González, nicknamed El R-1, was overlooked as the candidate of the regional boss of Reynosa and was sent to the "Frontera Chica," an area that encompasses Miguel Alemán, Camargo and Ciudad Mier – directly across the U.S.–Mexico border from Starr County, Texas. The area that Mejía González wanted was given to Samuel Flores Borrego, suggesting that the