People familiar with the episode said the use of the technology was not coordinated with the Federal Aviation Administration. Officials targeted what they thought was a drug cartel drone, but turned out to be a party balloon, they said.

The abrupt closure of El Paso’s airspace late Tuesday was precipitated when Customs and Border Protection officials deployed an anti-drone laser on loan from the Department of Defense without giving aviation officials enough time to assess the risks to commercial aircraft, according to multiple people briefed on the situation.

The episode led the Federal Aviation Administration to abruptly declare that the nearby airspace would be shut down for 10 days, an extraordinary pause that was quickly lifted Wednesday morning at the direction of the White House.

Top administration officials quickly claimed that the closure was in response to a sudden incursion of drones from Mexican drug cartels that required a military response, with Transportation Secretary Sean Duffy declaring in a social media post that “the threat has been neutralized.”

But that assertion was undercut by multiple people familiar with the situation, who said that the F.A.A.’s extreme move came after immigration officials earlier this week used an anti-drone laser shared by the Pentagon without coordination with the F.A.A. The people spoke on the condition of anonymity because they were not authorized to speak publicly.

C.B.P. officials thought they were firing on a cartel drone, the people said, but it turned out to be a party balloon. Defense Department officials were present during the incident, one person said.

The Defense Department and the Department of Homeland Security did not immediately respond to requests for comment. The F.A.A. declined to comment.

The military has been developing high-energy laser technology to intercept and destroy drones, which the Trump administration has said are being used by Mexican cartels to track Border Patrol agents and smuggle drugs into the United States.

The airspace closure provoked a significant backlash from local officials and sharp questions by lawmakers on Capitol Hill, including some Republicans, who expressed skepticism about the administration’s version of the events.

“At this point, the details of what exactly occurred over El Paso are unclear,” Senator Ted Cruz, Republican of Texas and the chairman of the Senate Commerce Committee that oversees the aviation agency, told reporters Wednesday after attending a closed-door briefing with Bryan Bedford, the F.A.A. administrator.

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Mr. Cruz and Senator John Cornyn, Republican of Texas, both said they wanted a classified briefing on the incident from the F.A.A. and the Defense Department.

Senator Jack Reed of Rhode Island, the top Democrat on the Armed Services Committee, also rejected the administration’s explanations.

“A ten-day shutdown of a major U.S. air corridor is an extraordinary step that demands a clear and consistent explanation,” Mr. Reed said in a statement. “The conflicting accounts coming from different parts of the federal government only deepen public concern and raise serious questions about coordination and decision-making.”

According to four people briefed on the situation, Pentagon and F.A.A. officials were set to meet on Feb. 20 to discuss the safety implications of deploying the military’s new anti-drone technology, which was being tested. But the F.A.A.’s urgency intensified after C.B.P. officials deployed the technology.

It was not clear if that incident alone prompted the F.A.A.’s decision to close the airspace over El Paso. F.A.A. officials did not respond to questions about the claims by Mr. Duffy and other administration officials that a subsequent drone incursion had necessitated the closure of the airspace starting at 11:30 p.m. local time. A Transportation Department spokesman did not respond to inquiries about whether a party balloon had been fired upon this week.

But according to the people briefed on the matter, at the time F.A.A. officials closed the airspace, the agency had not yet completed a safety assessment of the risks the new technology could pose to other aircraft. Two of the people added that F.A.A. officials had warned the Pentagon that if they were not given sufficient time and information to conduct their review, they would have no choice but to shut down the nearby airspace.

The F.A.A.’s initial closure announcement late Tuesday, which cited “special security reasons,” barred all aircraft from flying in the area around El Paso below 18,000 for 10 days — until one day after the Feb. 20 meeting had been scheduled to take place.

They did not alert the White House or the Pentagon ahead of time that they were shutting down the airspace, a senior administration official said, speaking on the condition of anonymity.

The move also blindsided El Paso officials.

“I want to be very, very clear that this should’ve never happened,” Mayor Renard Johnson of El Paso said in a news conference Wednesday morning. “You cannot restrict airspace over a major city without coordinating with the city, the airport, the hospitals, the community leadership.”

“That failure to communicate is unacceptable,” he added.

Federal agencies largely stayed mum on the controversy, even in its aftermath. Mr. Bedford, the agency’s administrator, declined to answer reporters’ questions following a closed-door briefing with senators at the Capitol Wednesday evening. Earlier Wednesday, a Pentagon spokesman repeated the military’s assertion that it had responded to a drone incursion.

A senior administration official, speaking on the condition of anonymity to address the dispute, challenged the claim of a failure of communication, saying that the Pentagon and the Department of Transportation had been coordinating with the aviation agency for months and that it had been assured that there was no threat to commercial air travel.

The official also said this was not the first time that cartel drones at the border had been disabled by military and immigration enforcement personnel acting jointly, describing their roles as two parts of an “ongoing interagency operation.”

The Trump administration has been vocal about its plans to fight Mexican drug cartels and neutralize the drones some are using as part of their operations, even as Mexico’s leaders reject claims that they have been involved in cross-border incursions.

“There is no information about the use of drones at the border,” President Claudia Sheinbaum of Mexico said in a morning news conference, shortly after news broke about the temporary closure of the El Paso airspace.

In July, Steven Willoughby, deputy director of the counter-drone program at the Homeland Security Department, testified before Congress that 27,000 drones had flown within 500 meters of the border over six months in 2024, piloted by organizations hostile to law enforcement.

Those drones can cause major disruptions to American infrastructure, Mr. Willoughby said, adding that his program works with the F.A.A. “to properly coordinate the use of each piece of equipment at specific locations and times to ensure that impacts to the national airspace system are minimized.”

The day after Mr. Willoughby’s testimony, Ms. Sheinbaum disputed his assertion, saying in a news conference that Mexican officials had observed the cartels using drones against one another inside Mexican territory, but not at the border. Speaking at the same news conference in July, Raymundo Pedro Morales Ángeles, Mexico’s navy secretary, insisted that the cartels’ drones “have not been detected at the border.”

In the United States, where many officials accept cartel drone incursions as established fact, some wondered why this particular incident would have prompted such an uncommonly sweeping response from the F.A.A.

“There have been drone incursions from Mexico going back to as long as drones existed,” Representative Veronica Escobar, the Texas Democrat representing El Paso in Congress, said at a news conference. “This is not unusual, and there was nothing extraordinary about any drone incursion into the U.S. that I’m aware of.”

In general, the F.A.A. goes to great lengths to avoid closing airports to traffic, because unplanned closures, even when they happen for just a few hours, can wreak havoc on air travel. Even in a high-risk security situation, F.A.A. airspace closures are usually limited.

On Jan. 3, for example, when the U.S. military captured Nicolás Maduro, the Venezuelan leader, and his wife, the F.A.A. issued emergency orders barring U.S. flights from operating in the region around Venezuela and closing U.S.-controlled airspace in other parts of the Caribbean for only 24 hours.

(http://www.autoadmit.com/thread.php?thread_id=5834052&forum_id=2#49665682)

They did not alert the White House or the Pentagon ahead of time that they were shutting down the airspace, a senior administration official said, speaking on the condition of anonymity.

(http://www.autoadmit.com/thread.php?thread_id=5834052&forum_id=2#49665689)