Los Zetas

Los Zetas (pronounced [los ˈsetas], Spanish for "The Zs") is a fractured Mexican criminal syndicate and designated terrorist organization, known as one of the most dangerous of Mexico's drug cartels. They are known for engaging in brutally violent "shock and awe" tactics such as beheadings, torture, and indiscriminate murder. While primarily concerned with drug trafficking, the organization also ran profitable sex and gun rackets.Los Zetas also operated through protection rackets, assassinations, extortion, kidnappings and other illegal activities.Although the organization was founded in Matamoros, Tamaulipas, they eventually established themselves in Nuevo Laredo, directly across the border from Laredo in Texas during the mid-2000s. The origins of Los Zetas date back to the late 1990s, when commandos of the Mexican Army deserted their ranks and began working as the enforcement arm of the Gulf Cartel. In February 2010, Los Zetas broke away and formed their own criminal organization, rivaling the Gulf Cartel. 

They were at one point Mexico's largest and most expansionist drug cartel in terms of geographical presence, overtaking their rivals, the Sinaloa Cartel, in physical territory.[However, since the mid/late 2010s Los Zetas have become fragmented and seen its influence diminish, with most factions absorbed by their regional opposition or eliminated.As of March 2016, Grupo Bravo (Bravo Group), Los Talibanes (The Talibans), and Zetas Vieja Escuela (Old School Zetas) had formed an alliance with the Gulf Cartel against Cártel del Noreste (Cartel of the Northeast).

Although fragmented, the Zetas' and Gulf Cartel's smaller offshoots, with their power struggles, continue to create a situation of extreme violence in their home state of Tamaulipas. As of 2025, The U.S. Department of State lists Tamaulipas alongside five other states in Mexico with a Level 4: Do Not Travel advisory