Read the article below. One of the most dangerous cartels has set up numerous gun manufacturing facilities in Mexico. They are building their own AR-15 rifles and selling them on the street for over $5000 US dollars each.
I will suggest a slight correction to the title of the article. The CJNG is the only cartel to have been caught with their own weapons manufacturing facilities. You can be 100% certain that the other large cartels are doing the same thing.