Rival drugs cartels battle for supremacy in Mexico

A little-known drugs cartel is challenging other gangs for dominance in Mexico following the capture and pending extradition to the United States of the drug lord Joaquin "El Chapo" Guzman. Reuters correspondent Dave Graham in Mexico City.

(Picture: State police officers stand guard at a checkpoint during a security operation in Puerto Vallarta in the western Mexican state of Jalisco on August 17, 2016. Credit: HECTOR GUERRERO/AFP/Getty Images).