The suspected terror plot, which would have attacked RAF Fairford, was intercepted after one of the suspects involved rang the police.
One of the five men arrested reportedly called 999 before the group were arrested on suspicion of explosives offences.
The Times reported that police are investigating whether the group members were acting as proxies for Iran.
It was initially reported that a farmer driving home in the early hours of Sunday morning tipped off police to the suspicious activity – but police were already on the scene by then, it has been reported.
The suspect’s motive in warning police is also being probed.
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It is unclear whether he got cold feet or whether it was part of their plan.
Earlier today, security expert Will Geddes told that the five men arrested near RAF Fairford may have been conducting a ‘dry run’ for a future attack.
Today, the head of Counter Terrorism Policing said that no improvised explosive devices were found in the three vans discovered near RAF Fairford, but a quantity of petrol was recovered.
Fears remain as the investigation continues.
Security expert Will Geddes told : ‘This seems to have been a dry run rehearsal before an attack.
‘Many terrorists get picked up during what we call hostile surveillance detection – when they’re taking photographs, driving routes, etc. I think this was their penultimate dry run before actually doing the attack itself.’
Head of UK counter-terrorism Policing Assistant Commissioner Laurence Taylor said earlier today: ‘We can confirm that no improvised explosive devices were found. However, a quantity of petrol was recovered.
‘Yesterday we released the five men on police bail. They remain under investigation and must adhere to strict conditions while we continue our work.
‘The safety of the public is at the forefront of our investigative decision-making, and this was certainly the case yesterday.
‘I understand why this development will have come as a surprise to many, but I’d like to reiterate that it was an investigative decision, and one which is grounded in experience and careful consideration of policing powers.’
Get in touch with our news team by emailing us at webnews@metro.co.uk.
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