Mexican authorities have announced a string of arrests of high-profile Zetas figures in recent months, and have said they believe a rift had emerged between Ivan Velazquez Caballero, a Zetas leader known as "El Taliban" nabbed by authorities last month, and Trevino, a Zetas capo known as "Z40" who has a reputation for being even more brutal. It was not clear which side Lazcano was on.
On Monday, the Mexican navy said it had arrested a regional leader for the Zetas, Salvador Alfonso Martinez, or "Squirrel," and believed he was involved in many of the Zetas' worst crimes. The high-profile arrests yield intelligence for other arrests, experts say.
Marines also recently caught the heads of the two main factions of the Gulf Cartel: Jorge Eduardo "El Coss" Costilla Sanchez and Mario Cardenas Guillen.
Associated Press writers Olga R. Rodriguez, Michael Weissenstein and Katherine Corcoran contributed to this report.
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