Over the last few weeks, a number of drones have mysteriously been spotted over three air bases used by the US Air Force (USAF) in the UK.
The unmanned aerial devices were first spotted on 20 November, over RAF Lakenheath and RAF Mildenhall, in Suffolk, and RAF Feltwell in Norfolk.
The unusual activity has prompted an investigation by civilian police and supported by the UK’s Ministry of Defence (MoD).
Around 60 British troops, including counter-drone specialists, have also been deployed to help defend the bases.
What we know about the drone sightings
The drones were first spotted in the vicinity of the three airbases last Wednesday.
Similar movements occurred again on Friday 22 November and “during nighttime hours” on Monday this week, a spokesperson for the USAF in Europe said.
The spokesperson said the number of aerial vehicles “fluctuated” and “varied between the bases”.
When asked by Sky News’ security and defence editor Deborah Haynes, the spokesperson said there has been “no impact to residents or infrastructure and [they] have not been identified as hostile”.
“However they are still continuously being monitored to ensure the safety and security of the installations.”
Haynes added that it remains “unclear how many drones are involved, who is operating them and why they are doing it” but it seems “sufficiently serious” for the UK to deploy military personnel.
Lakenheath is home to the 48th Fighter Wing, which the USAF describes as the foundation of its combat capability in Europe.
Mildenhall hosts the 100th Air Refuelling Wing, and Feltwell is a hub for housing, schools and other services.
The three bases are leased by the USAF from Britain.
What has the UK and US said?
The MoD said it is supporting the USAF response to the sightings, adding that it “takes threats seriously”.
This response is understood to include the deployment of around 60 military personnel, including members of the RAF Regiment’s Force Protection Wing, with specialist skills in countering drones to help protect the US bases and try to find out who is responsible for operating the unmanned aerial vehicles.
The RAF troops operate the ORCUS counter-uncrewed air system, which has the ability to “detect, track, identify and, if necessary, defeat hostile drones”, according to the RAF website.
US military units said they were still monitoring the airspace over the three bases on Tuesday evening.
Who could be operating the drones?
Pentagon spokesman Major General Patrick Ryder said on Tuesday it was too soon to draw conclusions about whether the drones were sent by hobbyists.
He admitted small drones are fairly common.
However, one security source told Sky News that the drone activity was “awfully coordinated.” Another said it was “odd” and “very weird.”
A US official, speaking on condition of anonymity, agreed that it did not appear that the drones were the work of hobbyists, adding that the US military would continue to investigate.
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Though it is unclear whether the drones had hostile intent, the sightings come as hostilities between Russia and Ukraine have significantly escalated.
Ukraine has struck targets inside Russia with intermediate-range missiles supplied by the US and Britain after President Joe Biden authorised the use of the weapons.
Soon after, President Vladimir warned he could hit back against countries supplying weapons being used against targets in Russia.
