Since the arrest of one of Mexico's most wanted drug lords — Knights Templar leader Servando Gómez Martinez, a.k.a. La Tuta — authorities have continued to crack down on the armed gangs seeking to fill the power vacuum created by La Tuta's arrest. One of these gangs is the Viagras.

VICE News exclusively obtained the first interview with Viagras leader Nicolás "El Gordo" Sierra since he went into hiding in December. Viagras members say they're simply a vigilante group, but Mexican authorities have found them to be involved in drug trafficking. We asked Sierra about the group and its origins.

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