UK PM Burnham says Iran likely behind RAF base incident: Is there evidence?

British Prime Minister Andy Burnham has said the UK’s security services have “strong indications” of Iranian involvement in the incident at a British Royal Air Force (RAF) station near Fairford this week in which five men were arrested before they were released on bail.

The five British men were spotted near the airbase and arrested on Sunday on suspicion of “terrorism” and explosives offences, before they were released.

The United States has used the British base to carry out operations in various conflicts, including to deploy bombers in its war against Iran.

Iran has strongly denied any involvement with the airbase incident, with Foreign Minister Abbas Araghchi saying British authorities are “barking up the wrong tree”.

So, what do we know about the incident, and is there evidence Iran played a role?

What happened at the airbase?

Authorities were alerted to suspicious activity near the base early Sunday morning, including three vans parked oddly and a group of hooded, masked men.

Police responded and arrested five British men in their early 20s in the nearby Whelford area, saying they were suspected of explosives offences. Counter Terrorism police later took over the probe and said the men were suspected of preparing “a terrorist act”.

The suspects were released on bail Monday, but remain subject to “stringent conditions on their movement and contact with others,” according to the United Kingdom’s head of counter terrorism policing, Laurence Taylor.

On Tuesday, after three days of investigations, including using a bomb disposal team, police said they had found no explosives in the vehicles that were parked the near the base, but had retrieved a “quantity of petrol”.

Who is linking the incident to Iran, and have they cited evidence?

Officials in the UK, the US and Israel have all pointed to Iran but offered no details.

Burnham on Wednesday spoke of “strong indications” of Iran’s involvement and said an “ongoing, complex and serious police investigation” is continuing.

However, the prime minister did not give any details on what the suspects were planning or why the UK thinks Iran was involved, saying only that he would “update people more in due course”.

In the US, President Donald Trump said the case “might be” Iran-linked and that the US had been keeping tabs on the suspects “for a long time”. Secretary of State Marco Rubio said the case “clearly involved the hands of a foreign actor”, without naming a specific state.

In Israel, Prime Minister Benjamin Netanyahu said Israel had forewarned the UK about a potential “Iranian-sponsored attack”.

How has Iran responded?

Iran has firmly denied involvement.

In a statement on Monday, Iran’s embassy in London said it “categorically rejects and strongly condemns” any attempts to link Iran to the individuals arrested near the airbase.

It said the spread of such “fabricated speculations” fuel “Iranophobia propaganda” and that Iran reserves the right to “take appropriate legal measures”.

On Wednesday, Iran’s Foreign Minister Abbas Araghchi said the UK was “barking up the wrong tree” by pointing to potential Iranian involvement.

Why has the UK released the suspects on bail?

It is unclear. Under British “counterterrorism law”, police can hold suspects for up to two weeks before charging them. However, if authorities find little evidence to support their initial suspicion of “terrorism”, they would have far less time – usually 24 to 36 hours, said Chris Phillips, a former head of the UK’s National Counter Terrorism Security Office.

“If it’s not an actual terrorist attack, then the police don’t have anywhere near as long to keep them in custody,” said Phillips. “I think the police just need more time to do their enquiries.”

Andrew Silke, professor of criminology at Royal Holloway, University of London, said the suspects could have also been released on bail while under suspicion of “terrorism” if “authorities feel relatively confident that these individuals do not pose an imminent danger of either carrying out or organising a terrorist attack”, such as if they had “peripheral” or “unknowing involvement”.

Afzal Ashraf, a visiting fellow in international relations and security at Loughborough University and a former senior Royal Air Force officer, said the bail release does not necessarily indicate that the “Iranian-involvement hypothesis has been rejected” but it does mean “police have judged that these individuals did not present any immediate danger”.

Taylor, the head of counter terrorism policing, said the men’s release on bail was an “investigative decision” based on “experience and careful considerations of policing powers.” He stressed that the men are bound by “stringent conditions on their movement and contact with others” as the investigation into them continues.

But their release drew backlash in the US from Trump, who said British authorities “should not have done that”.

“How do you give bail to a terrorist?” Trump asked.

Iran’s Araghchi appeared to suggest that the suspects’ release supported Iran’s position that it was not involved.

“I can confirm Iran’s belief that releasing supposed terrorists working for foreign states really says it all,” wrote Araghchi in a post on X.

What questions about the case are still unanswered?

Questions remain about the circumstances in which authorities were initially alerted to suspicious activity near the base, the extent to which they believe the suspects are linked to Iran and what the suspects may have been planning.

According to the BBC, police received two early-morning calls on Sunday regarding suspicious vehicles near the base, the first of which the media understands was made by one of the suspects themselves.

The Times of London reported that police are looking into the suspect’s motives for making such a call, including “whether he got cold feet or whether it was part of the plan”.

Authorities are also probing whether the incident was a form of “surveillance, a ‘dry run’ to test security or a stunt to send a message to the British government”, reported The Times.

Meanwhile, police have suggested they are looking into whether the suspects could have been unwittingly acting on Iran’s behalf.

In an updated briefing on Tuesday, Taylor said officials were examining whether the activity could have been “committed by proxies, or individuals either knowingly or unknowingly, working on behalf of a foreign state”.

He also spoke more generally about the “increasing breadth and complexity” of threats facing the UK, saying threats often emerge first as small-scale criminal activity, “committed by individuals whose primary aim is not terrorism but a quick financial gain”.

Phillips told Al Jazeera he believes the suspects could have been recruited online to carry out some type of malicious activity that falls short of a “terrorist attack”.

“It sounds as though these people have been paid online to do some naughty work”, such as “setting fire to something”, said Phillips.

He said both Russia and Iran have allegedly paid “stooges” to carry out such acts in recent years. “At first glance now, it seems that that may be the case, but time will tell,” Phillips added.

Royal Holloway’s Silke also said he believes the evidence suggests “a proxy explanation”.

“Certainly, there have been recent cases in Europe where individuals have been used unwittingly as proxies by foreign governments to carry out activities which have a hostile intent,” he said. “The UK authorities in this case may have assessed that something similar had happened here, and that the individuals involved had no inherent terrorist motivation themselves, but had been caught up unintentionally in a larger plot.”

Has Iran previously been accused of plots in the UK?

Yes. MI5 Director General Ken McCallum said in October 2025 that the agency had tracked “more than 20 potentially lethal Iran-backed plots” in the UK within a year.

McCallum alleged that Iran, along with Russia, has resorted to “ugly methods,” such as “surveillance, sabotage, arson or physical violence”.

British Security Minister Dan Jarvis has said Iran often uses criminal proxies to “obfuscate” its involvement in attacks, which have targeted Iranian dissidents and Jewish and Israeli people in the country.

In March this year, British police arrested four people on suspicion of helping Iran spy on the local Jewish community. The month after, police said they were probing possible Iran links to a series of arson attacks on Jewish targets ‌in London.

In June, two Romanian men whom British prosecutors said had acted as proxies for Iran’s government were handed lengthy jail terms for stabbing a British journalist of Iranian origin who wrote for an Iranian media outlet critical of Iran’s government.

Iran’s government has repeatedly denied involvement in any illegal plots or attacks on British.