The large criminal drug trafficking organizations do not control the arms traffic but rather, their distribution networks contact buyers in the US and they bring the arms into Mexico, according to a study by the Mexican Department of Justice (PGR).
The smuggling operation is carried out in a series of small shipments ("ant trails") and not big ones all at once, the PGR analysis indicates. "Up to now, no criminal organization, foreign or national, has been detected exclusively trafficking in arms," said the report.
The report also pointed out that Los Zetas, the armed branch of the Gulf drug cartel, has obtained most of their armament from Mexico's present federal administration. The official investigation assures that "in the US, there are no clandestine groups that sell arms, but along the length of the border with Mexico there are more than 12,000 sales establishments."