Heriberto Lazcano, alias "Z3," was a former commander in the Mexican special forces, before going on to head the Zetas’ drug trafficking operations. He was killed in a shootout with Mexican marines in October 2012.

Z3 was recruited in the late 1990s to work for the Gulf Cartel's security arm, the Zetas. He eventually became the group’s top security strategist.

By the time the Zetas broke from the Gulf Cartel in 2010, he was already managing several "plazas," or drug corridors. He was known as one of the most aggressive and ruthless members of the Zetas, an extremely violent group.

He was indicted in the District of Columbia, and the US put a $5 million reward for information leading to his capture.

The Zetas reportedly split into two rival factions around July 2012, one headed by Z3 and the other by Miguel Treviño Morales, alias "Z40." Reports of Z3's whereabouts during the split placed him outside of Mexico with the faction loyal to him being headed by Ivan Velazquez Caballero, alias "El Taliban." El Taliban was captured in San Luis Potosi state on September 26, 2012. 

Z3 was shot and killed by Mexican security forces on October 7, 2012 in Progreso, Coahuila.

Z40 was captured July 15, 2013. 

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