Five men have been arrested on suspicion of explosives and terrorism offences near RAF Fairford.
Here is what we know so far:
– How the incident unfolded:
Gloucestershire police say they were alerted to three suspicious vehicles travelling towards RAF Fairford at 12.45am on Sunday.
It is unclear what action was immediately taken.
A local farmer said she found three vans blocking a road in the nearby village of Whelford and called the Ministry of Defence Police but they did not answer the phone, so at 1.36am dialled 999 and armed police arrived 10 minutes later.
They arrested five men, pictured in some media outlets sitting on the ground handcuffed and shirtless.
The police operation was not intelligence-led, meaning that they did not know in advance that any plot was taking place.
At around 6am 85 households near the base were advised to evacuate while bomb disposal robots were used to examine the vans.
Counter-terrorism police took over the investigation and announced that the suspects had been arrested on suspicion of terrorism as well as explosives offences.
– The police investigation:
Investigators will be analysing the contents of devices seized from the suspects in order to establish the motivation for any potential plot and what they planned to do.
One line of inquiry will look at whether they were proxies tasked by Iran to try to attack the RAF base, which is used by the US military, reportedly including in its ongoing conflict with the Middle Eastern state.
The farmer who reported the vans to the police said she saw a group of around 10 men in the road, while counter-terrorism police said that five suspects were arrested.
They refused to give any further information on Sunday, although Gloucestershire police described the incident as “contained”.
– Reaction:
US president Donald Trump told reporters in Chicago that the suspects had been “looking to do big damage” to the base.
He also appeared to claim that the plot had been known about in advance, saying: “We had them under investigation.
“They were looking to do big damage to our fort, and working with the British worked out great.
“It may have been Scotland Yard, I don’t know. We worked with a lot of them. We had them under view for a long time, and we got them.”
Prime Minister Andy Burnham called the incident “deeply concerning” and said “the safety and security of the public is our first priority”.
On Monday Defence Secretary Wes Streeting said the UK and US will “always stand together against those who hate our freedom and those who wish us harm”.
He told the Labour Party conference: “Our friendship with America is the closest alliance of any two nations on earth, and we will always stand together against those who hate our freedom and those who wish us harm.
“What we saw yesterday from our security services, our armed forces and our police was just a small glimpse of the extraordinary work they do every day, around the clock and around the world, behind the scenes and without recognition, to keep our country safe.
“To all of them, from all of us, thank you.”
Foreign Secretary Ed Miliband said the suspected plot is a “reminder of the threats our country faces”.
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