Drone sightings forced officials to close the airspace at one of the largest US Air Force bases in the world over the weekend.
Drones flying around Wright-Patterson Air Force Base near Dayton, Ohio, led base officials to shut down the airspace for around four hours late on Friday and into early Saturday morning, a base spokesperson has said.
It is the first time drones have been spotted at the base, Robert Purtiman said.
No sightings have been reported since early on Saturday, he added.
Mr Purtiman said the drones ranged in size and did not impact any base facilities, but would not say how many were flying in the area.
It comes as police in Boston arrested two men accused of flying drones “dangerously close” to the city’s Logan Airport on Saturday night.
An officer using drone monitoring technology detected the aircraft and the location of the operators, authorities said.
A third man fled police and remains at large, they added.
The two men face trespassing charges and could face more charges and fines.
Boston police urged drone operators to adhere to federal safety guidelines in a post on social media, saying: “Even small drones pose significant risks, including the potential for catastrophic damage to airplanes and helicopters.
“Near-collisions can cause pilots to veer off course, putting lives and property at risk.”
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Drone sightings across eastern US coast
Swarms of drones have been sighted in eastern parts of the US since the middle of November, fuelling theories they could have been launched from an Iranian ‘mothership’ or by China.
Dozens of witnesses have reported seeing them across New Jersey, including near the Picatinny Arsenal military research and manufacturing facility and over president-elect Donald Trump’s golf course in Bedminster.
Sightings have also been reported in New York, with the runways at Stewart International Airport shut down for around an hour on Friday night because of drone activity in the airspace.
Calls for better technology to deal with drones
Legislators have demanded US federal and state authorities identify and stop the unmanned flights.
Officials at the FBI and the Department of Homeland Security (DHS) have said the sightings do not appear to be signs of foreign interference or a public safety threat.
But because they cannot say with certainty who is responsible for the swarms, or how they can be stopped, leaders of both political parties are calling for better technology and powers to deal with the drones.
‘The government knows what is happening’ – Trump
President-elect Trump has said the US military should tell the American public what is behind the drone sightings.
“The government knows what is happening,” Mr Trump said. “For some reason, they don’t want to comment. And I think they’d be better off saying what it is our military knows and our president knows.”
Speaking at a press conference in Palm Beach, Florida, Mr Trump said he “can’t imagine it’s the enemy” but did not go into further detail. He refused to answer when asked if he had received an intelligence briefing on the matter.
The White House has said a review of the reported sightings shows many of them were actually manned aircraft being flown legally.
New Jersey senator shares videos of mysterious ‘drones’
It comes after New Jersey Senator Andy Kim shared videos of what he described as multiple unidentified drones flying over the state.
Mr Kim posted four videos on his X account of lights moving across the sky, saying sometimes the lights were “solid white” while others “flashed of red and green”.
Mr Kim also said some of the unidentified objects appeared to be moving in “small clusters of 2-4” but he and officers often saw “5-7 lights” at a time.
