This is the moment suspected drones were captured hovering over RAF Marham after emergency sirens startled residents at nearby military bases.
Footage recorded on Friday evening appears to show three drones flying in a chevron formation, their white lights blinking intermittently near the base, which is home to the F-35 Lightning stealth fighter.
RAF Marham, near King’s Lynn in Norfolk, is staffed by more than 3,600 military personnel, civil servants and contractors.
The video surfaced after sirens sounded at RAF Lakenheath in Suffolk and were heard around RAF Feltwell in neighbouring Norfolk amid reports of suspected drone activity.
Residents said they heard what sounded like ‘war sirens’ at around 5.30pm on Friday, followed by a loudspeaker announcement in an American accent telling people to take shelter.
In one video, sirens can be heard echoing through the darkness of a resident’s garden, creating an unsettling scene.
The US Air Force confirmed that an alarm was triggered at RAF Lakenheath after ‘suspected unauthorised drones’ were reported near the base.
A spokesperson said on Friday: ‘This evening, USAF Security Forces personnel responded to suspected unauthorized drone activity over RAF Lakenheath.
‘No personnel, aircraft or infrastructure were affected.
Three suspected drones appear to hover near RAF Marham in Norfolk on Friday evening
Residents near the RAF bases filmed sirens sounding across their gardens in the darkness
RAF Marham houses the F-35 Lightning stealth fighter and employs more than 3,600 people
‘We continue to work closely with our host nation counterparts to ensure the safety and security of our U.S. service members, U.S. and host nation civilians, contractors, and all of our families.’
The Air Force appealed to anyone who had seen unusual or suspicious activity to contact local authorities.
The incident came just days after the US military moved at least 12 aircraft from another RAF station following a reported threat from Iran.
Nine US Air Force aerial refuelling aircraft left RAF Mildenhall in Suffolk on Monday and flew to bases elsewhere in Britain, Germany and Spain.
RAF Mildenhall hosts the 100th Air Refuelling Wing, the only permanent US refuelling wing in Europe. Its fleet includes KC-135 Stratotanker aircraft.
Three V-22 Ospreys, which are used by US special forces, were also relocated to RAF Lakenheath, where the sirens sounded on Friday evening.
A former RAF chief described the abrupt evacuation as ‘extraordinarily unusual’.
RAF Lakenheath had issued a separate drone alert on November 9, telling local residents and personnel living on the base to report sightings ‘immediately’ to security staff or police.
A light armoured vehicle and military personnel stand at the RAF Lakenheath entrance on September 27
The Suffolk base is home to the US Air Force’s 48th Fighter Wing, known as the Liberty Wing, which has almost 7,000 active-duty personnel, many of them stationed there.
Both installations subsequently increased security to ‘Force Protection Condition Charlie’, the second-highest alert level, used when intelligence indicates that a terrorist attack is likely.
The moves follow a similar withdrawal of bombers from RAF Fairford in Gloucestershire last month after an alleged Iranian terror plot was disrupted.
Security at US bases across Britain has been heightened since an incident at RAF Fairford in September.
Police discovered petrol, although no explosives, while searching vans near the Gloucestershire base.
The search followed the arrival of five men in three white vans during the early hours of the morning.
Two men were charged last month in connection with the incident. Prosecutors allege that one of them attempted to assist Iranian intelligence in Britain.
Tehran denied any involvement, but the US withdrew all of its B-1 bombers from RAF Fairford the following month.
A B-1B Lancer bomber at RAF Fairford, from where US strikes against Iran were launched
An Army bomb disposal robot examines the three white vans used by suspects at RAF Fairford last month
A spokesman for the Prime Minister previously said British bases were secure, adding: ‘The protection of our bases, both in the UK and across the world, is a top priority.’
The Conservatives, however, attacked Labour and accused Andy Burnham of displaying ‘weakness’ in response to the national security threat posed by Iran.
‘Labour cannot keep putting their heads in the sand,’ said Alicia Kearns, the Tory shadow foreign minister. ‘Iran continues to threaten Britain, hack our companies, and radicalise our citizens, yet this government responds with handshakes.
‘Until Burnham grows a backbone and takes defence seriously, our allies won’t trust us. Words mean nothing without real action.’
Mark Francois, a Tory defence spokesman, said: ‘Britain’s national security is under threat. Our adversaries are testing our resolve, our military infrastructure, and our relationships with our closest allies.
‘Yet Labour is showing weakness when Britain needs strength. And Burnham’s refusal to wake up to the threats we face is putting us in danger.’
Andy Burnham said last month that the activity at the Gloucestershire airbase was likely to have been coordinated from Iran.
Iran’s ambassador to the UK rejected the allegation that Tehran had been involved in any plot against the base.
Iran’s Revolutionary Guard Corps said in July that RAF Fairford, along with any other base used to launch attacks against Iran, would be considered a legitimate target.
Aircraft based at RAF Fairford were used in strikes against Iran during the conflict, which Donald Trump has said is now militarily ‘effectively over’.
The Ministry of Defence has been approached for comment.
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