Detectives have arrested a dual UK-Iranian national on suspicion of terrorism offences as part of an investigation into a suspected plot near RAF Fairford.

Counter-terrorism police said the 27-year-old man was arrested on Thursday in Westminster on suspicion of preparation of terrorist acts under section 5 of the Terrorism Act 2006.

A second man, 26, who is a UK national, has been questioned under caution.

Five men in their 20s were arrested in the village of Whelford, Gloucestershire, outside the RAF base in the early hours of Sunday after police were alerted to suspicious vans in the area. They were released on police bail.

Announcing the most recent arrest, Vicki Evans, the senior national co-ordinator for counter-terrorism police, said: “As we’ve made clear, we’re looking at all possible angles – including possible foreign state involvement.”

Counter-terrorism police said searches of two properties had been undertaken in Westminster, in London.

Evans added: “The investigation into circumstances surrounding events in Gloucestershire is hugely complex, and our specialist teams are interrogating multiple lines of inquiry.

More details soon …