Mexican President Claudia Sheinbaum has publicly demanded answers over the FBI's possible role in the 2024 capture of Sinaloa Cartel co-founder Ismael "El Mayo" Zambada, asking directly: "¿Quién mintió?" — who lied? Telemundo 20 Her question, posed at a recent press briefing, crystallizes a dispute that has simmered in Mexico City since Zambada turned up in US custody nearly two years ago under circumstances Mexican officials have never fully accepted.

The Mexican government has formally requested that the FBI clarify its possible participation in the operation that delivered Zambada to American soil, according to reporting from UnoTV. In parallel, Mexico's Fiscalía General de la República (FGR) — the federal Attorney General's Office — has opened new lines of investigation specifically examining whether US federal agents took part in what Mexican authorities characterize as an unauthorized cross-border operation. Investigators have already identified the physical location where Zambada and two associates were deprived of their liberty, a critical evidentiary marker in any Mexican prosecution of the underlying abduction, according to La Política Online.

A capture that never had an agreed narrative

Zambada's arrival in the United States in late July 2024 was framed by US authorities as a coup: the octogenarian co-founder of the Sinaloa Cartel, alongside Joaquín "El Chapo" Guzmán, delivered into custody without a shot fired. But the manner of his transfer — reportedly lured onto a plane and flown into New Mexico rather than extradited through conventional channels — left Mexican officials sidelined and, by their account, uninformed in advance. Sheinbaum's predecessor, Andrés Manuel López Obrador, voiced early skepticism about the operation's legality under Mexican sovereignty, a position Sheinbaum has now sharpened into a formal bilateral demand.

Zambada initially pleaded not guilty to drug trafficking charges before a federal court in Texas on July 26, 2024 Reuters. That plea held for roughly a year. By February 2025, his attorney indicated Zambada was seeking a plea agreement that would take the death penalty off the table Reuters. Reporting in mid-August 2025 from both Reuters and the Associated Press signaled the plea was imminent Reuters, and on August 25, 2025, Zambada formally reversed course, entering a guilty plea in US federal court BBC Reuters.

The guilty plea closed the American legal chapter of the case but opened, rather than settled, the Mexican one. A defendant's admission of guilt in a Texas courtroom addresses the trafficking charges against him. It does nothing to resolve the separate question Mexican prosecutors are now pursuing: whether the operation that placed Zambada in US hands violated Mexican law, and whether foreign law enforcement personnel operated on Mexican territory without the consent required under existing bilateral security arrangements.

Why the FGR's new inquiry matters now

The timing is notable less for coincidence than for sequencing. With Zambada's US prosecution concluded by plea, Mexican authorities are no longer constrained by the possibility that domestic findings could complicate an active American case. The FGR's identification of the site where Zambada and his two associates were held gives Mexican investigators a concrete locus for building a case around unlawful deprivation of liberty — a charge that, if substantiated against US personnel, would carry significant diplomatic weight regardless of whether any American ever faces trial in Mexico.

Sheinbaum's rhetorical question — who lied — points in at least three possible directions: US agencies that may have misrepresented the operation to their Mexican counterparts, Mexican officials who may have known more than they disclosed publicly, or intermediaries within the cartel structure who orchestrated Zambada's movements independent of either government's full knowledge. Mexican officials have not specified which they believe most likely, and the ambiguity itself has political utility, allowing Sheinbaum to press Washington for clarity while avoiding preemptive blame that could complicate the broader security relationship.

This dispute unfolds against a security partnership between Mexico and the US that has grown more transactional and less collegial in recent years, with both governments negotiating fentanyl interdiction, tariff threats, and troop deployment questions as parallel tracks. A formal Mexican demand for FBI clarification, backed by an active FGR investigation, adds a sovereignty grievance to that mix at a moment when Mexico has limited leverage to compel a substantive US response. Washington has not, per available reporting, issued a public reply to Mexico's request.

Whether the FBI or any other US agency responds substantively to Mexico's inquiry will likely depend on how much diplomatic cost Washington assigns to the dispute versus the operational value it places on shielding details of how a cartel figure of Zambada's stature was actually brought into custody.