The investigation began years ago after two drug dealers got into a car accident in a small Tennessee town. What followed was a series of secret wiretaps, a shootout with police and the discovery of drugs hidden in a tractor trailer that would eventually lead federal investigators back to cartel leaders in Mexico.

The investigation began years ago after two drug dealers got into a car accident in a small Tennessee town. What followed was a series of secret wiretaps, a

As part of its crackdown on gangs, the US Justice Department has offered $26m in rewards for Carteles Unidos leaders.