A number of drones have again been spotted over three air bases in Britain that are used by the United States Air Force.
US military units on Tuesday were still monitoring the airspace over RAF Lakenheath and RAF Mildenhall, in Suffolk, and RAF Feltwell in Norfolk after the unmanned aerial vehicles were sighted overnight, a spokesperson said.
The UK authorities are also working to help ensure the safety of the sites.
“I can confirm the situation is ongoing and our units continue to monitor the airspace and are working with host-nation authorities and mission partners to ensure the safety of base personnel, facilities, and assets,” the US Air Forces in Europe spokesperson said.
“To safeguard operational security, we do not discuss specific force protection measures, however we retain the right to protect our installations.”
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The development comes after unidentified drones were previously spotted between Wednesday and Friday of last week over the same three airbases – a highly unusual occurrence.
The US Air Force at the time said it was unclear whether the drones were considered hostile.
The Royal Air Force has been approached for comment.