‘Don Flaco’ Fights U.S. Extradition: Lawyers Say Alleged Sinaloa Cartel Chemicals Broker Was Held Incommunicado, and a Mexico City Judge Gave Authorities 24 Hours to Say Where He Was
Lawyers for José Ángel Rivera Zazueta, the alleged Sinaloa Cartel operator known as “Don Flaco” or “El Flaco,” have filed two amparo lawsuits in Mexico City federal courts to stop his extradition to the United States. They claim he was held incommunicado after his Sept. 22 arrest and accuse authorities of forced disappearance, Proceso reported on Monday, Oct. 5, 2026, citing court records.
Two amparos, a 24-hour order
According to Proceso, the defense first went to the Thirteenth District Judge for Criminal Matters in Mexico City. That judge initially granted a suspension in Rivera Zazueta’s favor and ordered authorities to report within 24 hours where he was being held, his legal status and his health. The defense says it has not been able to speak with him since his arrest. Proceso reported that some authorities have sent information to the court, but the judge has not disclosed which ones or what they said.
A second suit, before the Ninth District Court for Criminal Matters, challenges the provisional arrest warrant issued for extradition purposes. It also asks that he not be handed over to the United States while the case proceeds.
A public defender, despite private lawyers
The defense says the FGR knew Rivera Zazueta had private counsel since 2023, when Washington first accused him, but assigned him a public defender anyway. Because the extradition process began without his private lawyers taking part, they want it restarted, Proceso reported. The defense also acknowledges the risk of an “express” handover on national-security grounds, as Claudia Sheinbaum’s government has done before. None of these claims has been ruled on.
What Washington alleges
The U.S. Treasury first sanctioned Rivera Zazueta in January 2023. It accuses him of importing Chinese precursor chemicals for fentanyl and other synthetic drugs. On Sept. 29 it designated him again in its action against the Los Mayos faction of the Sinaloa Cartel, led by Ismael Zambada Sicairos, “Mayito Flaco.” Proceso says Treasury named two of his companies: Mia Centro Cambiario, a Mexicali currency exchange it alleges laundered cartel money, and Rivos Servicios in Culiacán. He has not been convicted of any crime in the United States.
N+ report on the Sept. 22 arrest:
Sources
- Proceso (Diana Lastiri), “Sobornos, favores políticos y narcotráfico: la red que EU vincula a ‘El Flaco’,” Oct. 5, 2026
- Video: N+ on YouTube
- Photos: FGR booking photo shared by Omar García Harfuch on X, via Proceso
Reported Oct. 5, 2026, from Proceso’s review of court records. The defense’s claims are allegations, the courts have not ruled on the amparos, and no extradition date has been announced.