Mexican President Claudia Sheinbaum has ordered an investigation into the role played by two US officials in a counter-narcotics operation in the northern state of Chihuahua.
The two died alongside two Mexican officials when their car crashed on their way back from an operation to destroy illegal drug labs, Chihuahua officials said.
Sheinbaum stated that neither she nor senior members of the federal security team had been informed about any joint US-Mexican operations.
The Mexican leader has been adamant that foreign officials can only operate on Mexican soil if given prior clearance at the federal level.
Sheinbaum has come under pressure from her US counterpart, Donald Trump, to do more to stem the flow of drugs from Mexico to the United States but she has insisted that Mexico's sovereignty cannot be breached.
On Monday, Sheinbaum noted, we did not have knowledge of any direct work between Chihuahua state and personnel from the US embassy and expressed the need to understand the legality of the operation.
A Chihuahua state official reported that the US nationals and two members of the Chihuahua State Investigation Agency (AEI) died when their vehicle skidded off the road into a ravine and exploded.
The US ambassador in Mexico, Ronald Johnson, described the two deceased as US embassy personnel, while Chihuahua State Attorney-General César Jáuregui explained they were engaging in training work as part of normal exchanges with US authorities.
Following the accident, Sheinbaum's government has requested information to determine if the operation may have breached Mexican national security laws, which prohibit joint operations without prior approval.
She emphasized cooperation with the US, including intelligence sharing, but reiterated that there are no joint operations on land or air without explicit consent.
