All US B-1 bombers previously deployed to Britain’s RAF Fairford have been withdrawn, the Pentagon confirmed on Sunday. The base, about 100 miles west of London, has been at the centre of speculation after a farmer in the area reported suspicious activity involving several vans and a group of men.

Residents of 85 nearby houses were evacuated amid an investigation into the report. Five men from London, all British nationals in their 20s, were also arrested on suspicion of explosives offences and suspicion of preparing an act of terrorism. They have since been released on tight bail conditions but remain under investigation.

UK officials have said there are strong indications that Iran was behind the incident. US Secretary of State Marco Rubio also spoke about the involvement of a foreign actor. Iran has denied involvement and has rejected the allegations. Around a dozen of the heavy bombers had been based at Fairford but have now been redeployed to bases in the US.

A Pentagon spokesperson said operational security had prevented Washington from confirming the movement of its aircraft and forces in real time. Fairford is one of a handful of bases in Europe from which the US flies its largest combat aircraft, which have been used to carry out strikes in the Middle East.

Earlier this year, Britain authorised the US to use the base for specific defensive operations against Iran.
Police said they were pursuing multiple lines of enquiry into the incident at Fairford, which included examining possible involvement of a foreign state or proxies. They said releasing the men on bail did not mean the investigation was over.

A separate 25-year-old dual British-Iranian national was arrested in London on Thursday in connection with the wider investigation. Three vans were searched and petrol was recovered but no explosive material. US President Donald Trump also criticised the decision to release the five initial suspects on bail, adding that he would not have released the men.

More information is expected to emerge about what happened at Fairford and what may have been the motivation as US and UK authorities continue to look into the incident.