Los Zetas are using smaller affiliate groups to attack their rivals in the west, and in doing so, they are revealing their larger strategic interests — and the value of these affiliate groups. On Dec. 24, a group of as many as 30 gunmen executed nine people in a small community in Concordia, Sinaloa state. According to the Sinaloa state attorney general's office, the culprits belong to an alliance of Los Zetas and the Beltran Leyva Organization. But the organization disintegrated into various competing groups after its leader, Arturo Beltran Leyva, died in December 2009. Therefore, the gunmen most likely belong to one of these splinter groups — probably a group called Los Mazatlecos. Four of the victims, including the son of a municipal council member, were kidnapped before being shot in a public area. Gunmen meanwhile killed five other individuals at a nearby grocery store.