The military reinforcement follows a Sept. 26 incident in which Coast Guard personnel returned fire after encountering gunfire from Mexico.
GARCENO, TX — About 500 U.S. troops are deploying to Texas’ Rio Grande Valley this week as federal forces reinforce operations along the U.S.-Mexico border following an exchange of gunfire involving Coast Guard personnel on the Rio Grande.
The deployment comes after Coast Guard Forces Rio Grande personnel encountered gunfire from the Mexican side of the border near Garceno on Sept. 26 while conducting joint interdiction operations with federal partners, according to the Coast Guard. Coast Guard personnel returned fire. No Coast Guard members or other personnel were reported injured, and no Coast Guard assets were damaged. The circumstances surrounding the shooting remain under investigation.
Law enforcement sources cited by NewsNation said roughly 500 troops were being sent into the Rio Grande Valley. Video obtained by the news organization showed troops being transported by Chinook helicopters to islands in the sector. Public reporting Friday did not establish whether all of the personnel involved in the new deployment were active-duty troops, National Guard members or a combination of forces.
The shooting has been described in news reports as involving suspected cartel members, but the Coast Guard’s statement did not publicly identify who fired the shots. The agency said only that its personnel encountered gunfire from the Mexican border. No arrests, injuries on the Mexican side or other confirmed outcomes from the exchange had been publicly announced as of Friday.
The Coast Guard said it is working with the U.S. Border Patrol, the Department of War and the Texas Military Department as part of the broader effort to secure the border and disrupt illicit activity. The agency said threats against its personnel and partner agencies are taken seriously and that the investigation into the Sept. 26 encounter is continuing.
The latest deployment adds forces to a border region where federal and state agencies already conduct overlapping security operations. The Texas Military Department has long supported law enforcement agencies along the Texas-Mexico border, including aerial detection and monitoring intended to help disrupt transnational criminal and drug trafficking organizations.
The Coast Guard also expanded its presence on the Rio Grande last year through Operation River Wall. Announced in October 2025, that operation sent additional personnel, response boats, shallow-water vessels, command assets and tactical teams to the river. The Coast Guard said the operation was designed to strengthen federal control along roughly 260 miles of the U.S.-Mexico border in eastern Texas.
Security officials have also raised concerns about drones operating in the border region. The Daily Caller News Foundation, citing U.S. Northern Command, reported that Joint Task Force Southern Border used a high-energy laser counter-drone system to bring down at least 11 cartel-operated drones from August through September. Officials said the drones presented threats to troops and Customs and Border Protection personnel operating in the area.
The Rio Grande Valley Border Patrol Sector covers a large stretch of South Texas, including hundreds of miles of river and coastline. Its geography includes sections of the Rio Grande where islands, dense vegetation and difficult terrain can complicate patrol and interdiction operations. Federal and state forces have previously conducted security operations on islands in the river that authorities have linked to smuggling activity.
Officials had not publicly released additional details Friday identifying the people responsible for the Sept. 26 gunfire or explaining how long the latest troop deployment would remain in place. The Coast Guard said the shooting remains under investigation as federal and state personnel continue operations in the Rio Grande Valley.
Author note: Last updated Oct. 2, 2026.