it is widely believed that El Mayo and Guzmán developed major differences, and that Zambada García betrayed his former partner to Mexican authorities in order to assume sole control over the cartel.

Supporters of this theory argue that Zambada Niebla’s dealings with the DEA and cooperation agreements were – and still are – all part of El Mayo’s plan to take Guzmán down and secure reduced sentences for his son and brother.

That would mean that El Vicentillo’s testimony marks a betrayal of Guzmán – with tacit US cooperation – but not of his father or the organisation.

El Mayo’s brother, Jesús Zambada García, who was the cartel’s accountant until his arrest in 2008, has also testified in the trial.