Iran “categorically rejects” it had any involvement in the suspected bomb plot on a British air base, its London embassy said on Monday.
The embassy condemned what it described as “unfounded and malicious speculations” about a potential link between Tehran and the arrest of five suspects in the vicinity of the RAF Fairford base in Gloucestershire, which houses US bombers.
Police are understood to be investigating whether any potential plot could be connected to Iran, which has used proxies to carry out crimes on British soil in the past.
The suspects arrested are all British nationals aged in their 20s and from London.
In its statement, the Iranian embassy said: “The embassy of the Islamic Republic of Iran in London categorically rejects and strongly condemns the recent unfounded and malicious speculations published by some British individuals and media outlets attempting to link Iran to arrest of five suspects in the vicinity of RAF Fairford base.
“The circulation of such fabricated speculations, particularly in the aftermath of the criminal acts of aggression committed by the United States and the Israeli regime against the Iranian people, will serve no purpose other than to fuel Iranophobia propaganda in the UK.”
A villager in Whelford dialled 999 after she saw three vans and a group of masked men near the base, and dozens of homes had to be evacuated as bomb disposal teams were called in.
On Monday, Counter-Terrorism Policing (CTP) said that multiple new lines of inquiry have emerged after investigators were working at the scene overnight.
The five suspects are being held under the Police and Criminal Evidence Act and officers have been granted an initial extension until later today to hold them in custody.
They are a 24-year-old from Camden, north London; three men aged 23, 24 and 25 from Westminster, and one aged 24 from Willesden, north-west London.
The local farmer who spotted the vans and a group of masked men initially called the Ministry of Defence police but there was no answer, so called 999 at 1.36am, and armed police arrived around 10 minutes later.
She said the police had “dropped the ball”, telling journalists: “Who knew that a farmer would have to roll their sleeves up and report the activity?”
On Sunday, US President Donald Trump told reporters the suspects were looking to “do big damage,” while on Monday, Defence Secretary Wes Streeting said the UK must not be “cowed by sabre-rattling from Iran” or allow the country to “dictate our foreign policy” while stressing it was “too early to attribute background aims.”
Aerial footage showed a bomb disposal robot spending hours inspecting three white vans, two of which had open rear doors. Large black barrels appeared to be scattered around.
A 400-metre cordon was erected and 85 evacuated households were unable to return home overnight. Cotswold District Council was seeking accommodation for some.
Prime Minister Andy Burnham said the incident was “deeply concerning” and that the government would “always take every step necessary” to protect people.
Investigators will now be working to analyse any devices seized from those arrested to establish details of any plot and any potential motivation.
The arrests come amid heightened concerns around the threat from hostile states to the UK, with Russia and Iran among those that have used proxies to commit crimes on their behalf on British soil.
In March, officials said the number of national security cases involving activity by hostile states including Iran increased 50% in the six months to December 2025.
That same month, after then prime minister Keir Starmer granted permission for “defensive” US action against Iranian missile sites from UK bases, four American bombers landed at RAF Fairford and the US started using British bases for “specific defensive operations.”
Separately, a spate of anti-Semitic attacks on Jewish sites in London this year were claimed by a group called Harakat Ashab al-Yamin al-Islamia, the Islamic Movement of the Companions of the Right (HAYI), which is thought to be backed by Iran.
Support for Iran’s Islamic Revolutionary Guard Corps (IRGC) and HAYI was banned in July by Starmer.
Under the state threat powers, anyone supporting or assisting the groups will face a maximum punishment of 14 years in prison, but ministers will need parliamentary approval first.
The Fairford incident also took place against the backdrop of ongoing war between the US and Iran.