The expansion was not undertaken in order to increase Los Zetas' drug trafficking or prostitution operations, but rather to enter into the business of coal mining.



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The state of Coahuila is rich in coal, and mining the fuel offers Los Zetas a more-or-less legal revenue stream.

The coal is mined by Los Zetas' own poorly paid workers, or bought at a low price from small miners, who are forced to sell their product to the gang. Los Zetas then resells the coal to a state-owned company for a profit that is estimated to be 30 times greater than the initial investment.

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This setup is proving hugely lucrative for Los Zetas. Humberto Moreira, the former governor of Coahuila, claimed recently that the practice has become even more profitable for the cartel than drug-running.