But Los Zetas stands out. “The Zetas were involved in 20 different criminal activities,” George Grayson, an expert on the Zetas and professor of government at the College of William & Mary, said.

The Zetas were formed by former Mexican special forces as the security arm of another cartel. From there, they muscled their way to the top of the lucrative drug business and now control the trade ...

5 minute read Handout photo released by Mexican Navy showing the alleged head leader of Mexican drug cartel "Los Zetas", Miguel Angel Trevino Morales, aka "El Z 40" in Mexico City on July 16, 2013.