The Pentagon has withdrawn at least a dozen aircraft from a Royal Air Force base in Suffolk after Iranian threats to US military sites.
Nine air refuelling tankers were relocated from RAF Mildenhall, in Suffolk, to other bases in the UK, Germany and Spain on Monday.
The evacuation was prompted by threats from Iran that US officials were alerted to on Monday, according to the Wall Street Journal. However, the Telegraph understands there is no direct or imminent threat to the base.
It follows the withdrawal of US bomber planes from RAF Fairford, in Gloucestershire in September, after a suspected Iranian-linked terrorism incident near the air base, which was housing jets the US has used to strike Iran.
Sir Ken McCallum, the head of MI5, has alluded to the possibility that Tehran has previously plotted against other British military bases, telling journalists at his annual address last month that the incident in Fairford was “not unique”.
Tehran’s Islamic Revolutionary Guard Corps warned in July that “any base used for aggression against Iranian territory is a legitimate target for us”, and claimed the US was “resorting to using B-1 aircraft flying from Fairford air base in England” because its missile stockpiles had been depleted.
It also accused Britain of causing the “misfortunes of the people of our region” by “dismantling Islamic countries … imposing despotic governments” and “worst of all” creating the “disaster of Israel”.
It is unclear if new intelligence suggests a fresh plot against US military sites in Britain, but the security level at both RAF Mildenhall and RAF Lakenheath has been upgraded to FPCON Charlie, the Pentagon’s level for intelligence suggesting a form of terrorist action is likely.
It is understood the UK security community believes that whatever Tehran’s intentions, it does not have the capability to launch a serious drone or explosive attack on a British military base.
The US military has taken an extremely risk-averse approach to any threats against its military assets or personnel. Analysts point out that merely threatening a base housing US assets may be enough for Tehran to disrupt the Pentagon’s military calculations.
RAF Mildenhall hosts the 100th Air Refueling Wing, the only permanent US refuelling wing in the European combat zone. It operates the KC-135 Stratotanker.
Flight data reviewed by the Telegraph showed that nine US Stratotanker refuelling jets had departed RAF Mildenhall by Monday night.
One flew to RAF Prestwick in Scotland and three to Moron de la Frontera in southern Spain, which hosts US Air Force units. Five flew towards Germany, with four landing at Spangdahlem Air Base and one at Ramstein, the largest US Air Force installation outside of the US.
All of these aircraft used their transponders to broadcast their locations. Some military flights do not use their transponders for operational security reasons, meaning that more aircraft could have potentially left the Suffolk air base.
A US-European command official said: “US Air Force aircraft rotate between installations and operating locations for a variety of reasons, including training and real-world requirements.
“US military aircraft are hosted in accordance with access, basing, and overflight agreements with our allies and partners. Due to operations security, we will not provide further information on movement of assets.”
A Ministry of Defence spokesman said: “We do not routinely comment on the activity of other nations. Aircraft and other assets move regularly according to operational requirements.”
Asked about the incident on Tuesday morning, Lucy Powell, the Education Secretary, told Sky News: “I can’t comment on those sort of live operations as you know, but we’re constantly keeping the security of our bases under review.
“And as we’ve seen with other cases recently, we take firm and quick action where we need to.”
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