President Claudia Sheinbaum said Mexico sent a diplomatic note to the U.S. Embassy seeking to know why U.S. agents participated in a field operation.

Mexican President Claudia Sheinbaum said she requested details about a security operation in Chihuahua involving U.S. agents, two of whom were killed.

Sheinbaum’s comments come at a pivotal time in U.S.-Mexico relations.

The two died in a car crash after a Mexican-led operation to destroy a clandestine drug lab.

President Claudia Sheinbaum said Mexico sent a diplomatic note to the U.S. Embassy seeking to know why U.S. agents participated in a field operation.