The criminal groups have used the technology to modernize their operations, smuggle fentanyl, organize migrant border crossings, surveil territory and wage war on rival cartels and Mexican authorities.

U.S. officials initially said the airspace was closed to halt an incursion by Mexican cartel drones, though others familiar with the situation later put that explanation in doubt.

Steven Willoughby, deputy director of the Department of Homeland Security’s counter-drone program, told Congress in July that cartels use drones almost daily to move drugs across the border and to monitor Border Patrol agents.

According to their data, in the last six months of 2024 more than 27,000 drones were detected within 500 meters (1,640 feet) of the U.S. southern border, mainly at night.

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