Mexican President Claudia Sheinbaum demanded explanations from the United States on Monday after two US Embassy officials and two Chihuahua state investigators died in a car crash the previous day. The incident occurred as the officials returned from an operation to dismantle clandestine methamphetamine laboratories in the municipality of Morelos, in southwestern Chihuahua.

The victims included Pedro Ramón Oseguera Cervantes, regional director of Chihuahua's State Investigation Agency (AEI), and his bodyguard Manuel Genaro Méndez Montes. The US officials, described as instructors from the US Embassy in Mexico City, were not publicly identified. Chihuahua Attorney General César Jáuregui stated that around 2 a.m. Sunday, the lead vehicle in a five-vehicle convoy skidded on the Chihuahua-Ciudad Juárez highway, fell into a ravine, and exploded. The convoy was traveling through rugged mountain terrain after the operation, which followed three months of investigation by state and federal defense officials using drones to locate the labs.

Sheinbaum, speaking at a press conference, said her administration was unaware of any collaboration between Chihuahua state authorities and the US Embassy. "It was not an operation that the security cabinet was aware of... We were not informed; it was a decision by the Chihuahua government," she said. She emphasized that Mexican law requires federal authorization for foreign involvement in security operations, and her government would review whether national security laws were violated. The president noted that while Mexico shares intelligence with the US, there are "no joint operations on land or in the air."

The US officials had provided training on drone operations at a separate location after the lab destruction, which involved around 80 Mexican personnel, and were picked up before the return trip. Jáuregui described their role as routine training support for state efforts against cartels. Authorities found no evidence of foul play or cartel involvement in the crash.

US Ambassador to Mexico Ronald Johnson expressed condolences on social media, calling the deaths a "solemn reminder of the risks faced by those Mexican and US officials who are dedicated to protecting our communities." The US Embassy confirmed the staffers were supporting Chihuahua's anti-cartel efforts but declined to provide further details on their identities or agency.

Sheinbaum plans to arrange a meeting between Johnson and Mexico's foreign minister to discuss the matter. The incident highlights ongoing sensitivities in US-Mexico security cooperation, where training and intelligence sharing are common but direct foreign involvement remains controversial under Mexico's sovereignty-focused policies.

Chihuahua, a major battleground for cartels like Sinaloa and Jalisco New Generation, has seen persistent violence tied to drug production and trafficking. The destroyed labs contained tons of precursor chemicals, though no suspects were present.