According to the U.S. official, Trevino Morales was in charge of Nuevo Leon, Piedras Negras and other areas until March 2007, when he was sent to the city of Veracruz following the death of a leading Zeta in a gunbattle there.
That same year, Trevino Morales and Lazcano began pushing for independence from the Gulf cartel after cartel head Osielo Cardenas Guillen’s extradition to the U.S.
The Zetas split from the Gulf cartel and by 2008 had operations in 28 major Mexican cities, according to an analysis by Grupo Savant, a Washington-based security think tank.