The Beltrán Leyva Organization (BLO), responsible for bringing violence to comparatively calm central Mexico, dissolved after the arrest of its leader, Sergio Enrique Villareal Barragan (“El Grande”). In its place emerged Grupo Pacifico Sur, one of two groups formed by former BLO operatives. Hector Beltrán Leyva, a former BLO leader, created Los Zetas-allied Pacifico Sur, which controls territory along the Pacific Coast, stretching from the south almost all the way to the US border (see map here).
A rival group born from the decline of BLO was led by Edgar “La Barbie” Villarreal, who was arrested in August 2010. Many other former BLO members opted to return to Sinaloa, which was allied with BLO in the past.