British counterterrorism police are investigating a suspected terrorist plot near RAF Fairford in Gloucestershire after five British men were arrested early Sunday near three vans traveling toward the air base, which has been used by US forces during the Iran war.
The men, aged 23 to 25 and all from London, were arrested on suspicion of offenses under the Explosives Act and preparation of a terrorist act, then released on bail Monday under what police described as stringent conditions.
Investigators are examining suspected explosives and possible links to foreign states or militant groups, while stressing that no motive or state-backed connection has been established.
Police were alerted after residents reported suspicious vehicles near Whelford shortly after midnight.
A local farmer said she encountered vans blocking a road and saw a group of hooded or masked men flee after noticing her car.
Armed officers responded, bomb disposal robots examined the vehicles, and authorities established a 400-metre cordon.
About 85 households in Whelford were advised to evacuate as the investigation continued.
Counter Terrorism Policing said significant resources, including military assets, remained deployed around the area.
Laurence Taylor, head of UK Counter Terrorism Policing, said investigators were considering whether individuals may have acted, knowingly or unknowingly, on behalf of a foreign state.
Possible links to Iran, Russia or militant groups are among the lines of inquiry.
Iran’s embassy in London rejected suggestions of Iranian involvement, condemning what it called “unfounded and malicious speculations” linking Tehran to the arrests.
British officials have not attributed responsibility.
Defense Secretary Wes Streeting said it would be irresponsible to speculate on Iranian involvement, while Foreign Secretary Ed Miliband said Britain would act against Iranian proxies.
US President Donald Trump said the suspects had been under observation and were “looking to do big damage” at the base, raising questions about when authorities became aware of the suspected plot.
British police, however, said the arrests followed a resident’s report of suspicious vehicles.
Streeting later said the reporting resident had only a partial picture, without elaborating because of operational security.