Mexico sent 500 Army Soldiers supported by Blackhawk helicopters to the Rio Grande Valley in October 2026 to support a mirrored counter-transnational criminal organization (C-TCO) operation with the United States after someone fired on U.S. Coast Guard personnel conducting migrant interdictions in the area, according to a news release from Mexico’s Secretariat of National Defense (DEFENSA).
The Mexican troops also carried unmanned aerial systems (UAS) and counter-UAS (C-UAS) systems to deter drug smuggling along the 1,345 kilometer-long border separating Mexico and the U.S. “This bilateral cooperation mechanism is carried out under the principles of reciprocity, shared and differentiated responsibility, mutual trust, and respect for decisions and sovereign territories,” DEFENSA’s October 4 release stated.
On September 26, shots fired from the southern bank of the Rio Grande during the Coast Guard operation resulted in return fire from the Guardsmen. No injuries or damaged equipment were reported. The incident occurred near Garceño, Texas, a town of about 400 in Starr County about 97 kilometers west of McAllen with shallow river crossings — a trouble spot for border crossings and TCO activity, according to Clarín, an Argentinian newspaper.
At the time of the shooting, Mexico and the U.S. were conducting mirrored operations on either side of the border involving Mexican Navy personnel and U.S. troops under the jurisdiction of U.S. Northern Command (USNORTHCOM).
After the shooting, USNORTHCOM ordered an additional 500 troops to the area. U.S. Ambassador to Mexico Ronald Johnson posted on X that the U.S. “is helping to coordinate with Mexican forces that are being deployed in the border area where shots were fired against elements of the United States Coast Guard.”
“Mexican military commanders will communicate directly with the U.S. forces deployed. Together, we intend to patrol both sides of our shared border, protect our communities and disrupt the operations of criminal and terrorist organizations. Any threat from criminal or terrorist elements on either side of the border will be addressed swiftly,” he added, according to Fox News.
Mexico and the U.S. have worked closely together on C-TCO activities since 2024 when Mexican President Claudia Sheinbaum assumed office. Sheinbaum has aggressively confronted TCOs in Mexico, especially the powerful Sinaloa Cartel. Her government has shuttered fentanyl labs and deterred illegal immigration and smuggling activities along the border. Since early 2025, cross-border migration has slowed to a trickle and TCOs have found it increasingly difficult to smuggle drugs and commit other crimes. Recently, the Joint Task Force-Southern Border announced that its operations had downed about 300 cartel drones along the border with more each month being disabled and destroyed.