Counter-drone lasers will now be able to be used along the southern border after the Federal Aviation Administration agreed with the Pentagon Friday that they are safe, so additional airspace closures aren’t expected.

The FAA and Defense Department have signed an agreement outlining the safety precautions that will be employed when these lasers are used to protect travelers. Earlier this year, the FAA twice shut down parts of Texas airspace after anti-drone lasers were deployed.

In early February, the FAA closed the airspace around the El Paso airport for several hours after another agency used a counter-drone laser without notifying the aviation safety regulator. That left many travelers scrambling to find new flights. A second more limited airspace closure followed the military shooting down a drone owned by U.S. Customs and Border Protection.

A demonstration of the lasers conducted last month at the White Sands Missile Range in New Mexico convinced the FAA that they can be used safely.

“We will continue working with our interagency partners to ensure the National Airspace System remains safe while addressing emerging drone threats,” FAA Administrator Bryan Bedford said in a statement.

Lawmakers were concerned about an apparent lack of coordination after the Pentagon allowed Customs and Border Protection to use an anti-drone laser in early February without notifying the FAA.

On Feb. 26 the military used the laser to shoot down a “seemingly threatening” drone flying near the U.S.-Mexico border. It turned out the drone belonged to Customs and Border Protection, lawmakers said.

That led the FAA to close the airspace around Fort Hancock, about 50 miles (80 kilometers) southeast of El Paso.

The Trump administration has said it was working to halt an incursion by Mexican cartel drones. U.S. Army Brigadier General Matt Ross said that this agreement will allow the use of the most advanced tools to defend the homeland.

“By working hand-in-hand with the FAA and our interagency partners, the Department of War is proving that these cutting-edge capabilities are safe, effective, and ready to protect all air travelers from illicit drone use in the national airspace,” Ross said.

Josh Funk, The Associated Press