This week's escape of drug kingpin Joaquin "El Chapo" Guzman has turned glittering success into abject failure for Mexico's President Enrique Peña Nieto.
The sophisticated tunnel built under the noses of prison officials has made a mockery of security and raised suspicion of official complicity. Guzmán's cartel is reportedly the main supplier of cocaine and heroin to the United States, and his show of power is a blow to international cooperation. We follow the story on both sides of the border.