Sixth arrest in RAF Fairford probe as UK PM says Iran played a "part" in suspected plot

A British-Iranian man has been arrested in London in connection with a suspected terror plot at RAF Fairford, British counter-terror police said on Thursday, in the sixth arrest linked to the security scare at the US-used airbase.

The man, in his twenties, was taken into custody in the borough of Westminster on suspicion of preparation of terrorist acts. He is understood to have been put under surveillance after five men were arrested near the airbase in the early hours of Sunday.

The alert began when three white vans were seen heading towards RAF Fairford in Gloucestershire, which has been used by American bombers to strike Iran during the Middle East war. A local resident who called the police said she saw masked men near the vans, which were blocking a road in a nearby village.

Five British nationals, all in their twenties, were arrested on Sunday on suspicion of explosives and terrorism offences. They were released on bail on Monday as the investigation continued. Police said they found a quantity of petrol but no explosive devices in the vans.

Prime Minister Andy Burnham said on Wednesday there were "strong indications" that Iran played a part in what happened at RAF Fairford. "We have been waiting to confirm what we could say, but we can now confirm our belief that Iran played a part," he told broadcasters, adding that it remained "an ongoing, complex and serious police investigation". He also said he "wouldn't hesitate" to recall Parliament over the incident if necessary.

US officials were already aware of an Iran-linked plot to attack the bomber aircraft and kill personnel at the base, according to officials cited by the Wall Street Journal. A branch of the Islamic Revolutionary Guard Corps had recruited UK nationals as proxies, US officials said. US Secretary of State Marco Rubio had earlier said the suspected plot "clearly involves the hand of a foreign actor".

Iran's embassy in London said it "categorically rejects and strongly condemns" the speculation, calling it unfounded. The plot was foiled when one of the suspects himself called the police, the Times reported.

Using proxies to plot an attack on a British military installation would mark a significant escalation, given that Britain is not directly at war with Iran. Iran has targeted British bases abroad during the war, including Diego Garcia in the Indian Ocean and Akrotiri in Cyprus.