Military Cites ‘Confusion’ After Landing on Mexican Beach and Declaring It U.S. Property

U.S. defense officials say a group working near the border mistakenly posted Department of Defense warning signs on a beach in Mexico, triggering confusion and a quick response from Mexican authorities.

On Monday, Nov. 17, signs appeared in English and Spanish at Playa Bagdad in Tamaulipas, on the Mexico side of the U.S.–Mexico boundary. The notices warned that the area was “Department of Defense property,” labeled it a “restricted area,” and cautioned against trespassing, according to The Daily Beast.

Photos of the signs spread rapidly online, with some users calling the move an “invasion.” Mexican Navy personnel arrived at the site — roughly 12 miles south of the border — and removed the markers after determining they had been placed in the wrong location.

Mexico’s Ministry of Foreign Affairs and Ministry of the Navy later confirmed in a joint statement that six signs had been taken down as a preventive measure. The agencies said they could not immediately verify who had installed them, My San Antonio reported.

A U.S. official at Joint Base San Antonio, a nearby military installation, said the signs were put up by contractors operating in the area. The official attributed the mistake to shifting water depth and terrain, which allegedly led to a misread of where the international boundary sits. The base said it would coordinate with relevant agencies to prevent similar confusion going forward.

The incident appears tied to the U.S. military’s broader work along the southern border, including efforts to establish a National Defense Area (NDA) spanning parts of Hidalgo and Cameron counties. The NDA is part of the Trump administration’s push to tighten border control and create zones treated as military-protected property.

After a visit to an NDA site earlier this year, Defense Secretary Pete Hegseth told troops that unauthorized entry into such zones would be treated like entering a military base and could result in detention by U.S. forces working alongside border agents.

According to My San Antonio, the NDA is expected to be administered by the U.S. Air Force through Joint Base San Antonio. The Pentagon has directed further questions to the Air Force.

Playa Bagdad, where the signs appeared, is a well-known beach outside Matamoros, across from Brownsville in Texas. The shoreline is popular with locals and visitors and is also a common viewing spot for SpaceX launches from the region, My San Antonio noted.