Mexico’s attorney general-linked security dispute with the United States intensified Monday after President Claudia Sheinbaum said her government sent a diplomatic note over unauthorized US participation in an anti-narcotics operation in Chihuahua. Sheinbaum said the federal government did not know the US officials were involved until after a crash on 19 April killed four officials. Mexico wants the episode treated as exceptional, not repeated.
Unauthorized presence at Chihuahua operation draws a sharp warning
The crash happened after the anti-narcotics operation in the northern state of Chihuahua, where two US officials and two Mexican officials died. Sheinbaum said at her daily morning press conference that Mexico told the United States the involvement of those people had not been known to the federal government. She added that Mexico hopes this was an exception and that the arrangement should not happen again.
Mexico said it requested that, from now on, its constitution and national security law be followed, and Sheinbaum said the United States had indicated agreement. The issue is sensitive because the presence of US personnel in anti-cartel work has long been one of the most delicate parts of bilateral security cooperation.
Accreditation questions add to the tension
Mexico’s security cabinet said Saturday that the US officials did not have formal accreditation to take part in security activities in Mexico. The cabinet also said one of them entered the country as a tourist. Those details hardened the official response and sharpened the dispute over how the operation was carried out.
The deaths of the two Americans reopened friction over cooperation that Mexico accepts in some forms but not in others. Sheinbaum has said she welcomes intelligence sharing and security coordination, but will not accept US agents or forces participating in operations on Mexican territory. That position now sits directly alongside a case in which the federal government says it was not informed in advance.
Immediate reactions inside Mexico’s government
“What we told [the US] was that the federal government didn’t know about the involvement of these people [in the operation] and we hope that it’s an exception, ” Sheinbaum said. Her remarks framed the message as both a correction and a warning, with the emphasis on preventing any repeat.
In the same briefing, Sheinbaum said Mexico had asked that the legal framework governing national security be followed going forward. The government’s language left little room for ambiguity: cooperation may continue, but only inside the rules Mexico says apply on its territory.
What this means for bilateral security cooperation
The episode comes at a time when Donald Trump has repeatedly pushed for greater US military force against Mexican cartels and has threatened unilateral action if Washington believes Mexico is not doing enough. That pressure makes the Chihuahua case especially fraught, because it touches both security policy and sovereignty.
For now, the key question is whether both sides can contain the fallout and restore a tighter process for any future cooperation. Mexico’s message is blunt: the attorney general-linked security line, as the government is presenting it, must hold, and the Chihuahua incident should not be repeated.
