The Mexican government in early October 2026 said it sought increased cooperation and communication with the United States after an incident in which the U.S. Coast Guard vessels and crews operating in the Rio Grande Valley came under fire from unidentified combatants in northern Mexico.
Mexico’s Secretariat of the Navy (MARINA) stated in an October 3 news release that the September 26 incident, in which no one was injured nor any equipment damaged, occurred during an ongoing joint exercise where the North American partners were engaged in “mirror operations.” Those operations, MARINA said, “bear witness to [both nations’] commitment to strengthen border security, improve detection capabilities and safeguard the corresponding sovereignty.”
MARINA, through its naval sector in Matamoros, Tamaulipas, was carrying out an exercise within Operation Sable involving 159 naval elements, 11 vehicles and two drones, according to the release. U.S. Northern Command later announced a deployment of about 500 troops to the border as part of Operation Burning Vanguard, the MARINA release stated.
“Based on the above, the relationship between the two countries is conducted through the four axes of the binational policy of the Government of Mexico: respect for sovereignty, shared responsibility, mutual trust and cooperation without subordination,” the MARINA release stated.
MARINA will continue to maintain surveillance and security operations on the border, the release stated, and MARINA emphasized “that any mechanism for cooperation or exchange of information is developed through the established institutional channels, with full respect to the sovereignty, attributions and jurisdiction of each country.”
Stars and Stripes, a U.S. military newspaper, reported that Coast Guardsmen were intercepting migrants crossing the Rio Grande along with other federal agents when they were shot at from the southern bank and returned fire.
USNORTHCOM, through its Joint Task Force-Southern Border (JTF-SB), confirmed the incident in an October 2 news release when announcing Operation Unified Resolve, “an ongoing effort to rapidly reinforce U.S. forces and federal partners operating in the Rio Grande Valley as part of Operation Ardent Vanguard.”
The hundreds of JTF-SB service members and associated equipment in Operation Unified Resolve were repositioning to the Rio Grande Valley “to strengthen border security operations, increase the joint force’s ability to respond to threats and support federal law enforcement partners operating along the Rio Grande,” the JTF-SB release stated. “Operation Unified Resolve will increase patrol capacity, reinforce key areas, provide additional monitoring and detections capabilities, and reinforce security of critical location in support of the Department of Homeland Security and U.S. Customs and Border Protection,” the release stated.