Mexico has extradited to the US a senior member of the Sinaloa drug gang formerly headed by Joaquin “El Chapo” Guzman. Damaso Lopez aka “The Graduate” is alleged to have been responsible for organising Guzman’s escape from a high security jail in 2001. He then joined the cartel and became one of the drug lord’s closest allies. He was captured last May and is seen by the US as a key witness in the case against Guzman who is in a US jail. Damaso Lopez was arrested last year in Mexico city.