London — British counterterrorism police officers arrested four Iranian men over an alleged plot to attack an unspecified target, and three others over an undefined national security threat, London's Metropolitan Police said Sunday. The government called the operations the biggest "counter-state threat and counterterrorism" in years.
The Met, as London's police force is often known, said five men between the ages of 29 and 46 were detained Saturday in various parts of England under the Terrorism Act on suspicion of preparing "a terrorist act."
Four are Iranian citizens and the nationality of the fifth was still being established. Police said the attack plot was targeting a single location that was not being named "for operational reasons." They said people at the premises in question were being given "advice and support."
All the suspects were being questioned at police stations and had not been charged as of Monday morning. Police said they were searching several properties in London, the Manchester area in northwest England, and Swindon in western England.
Police forensic officers search a house in Rochdale, in northwest England, on May 4, 2025, as London's Metropolitan Police said five men, including at least four Iranian nationals, were arrested in pre-planned counterterrorism raids in the Greater Manchester area, Swindon, and London, as part of an investigation into "a suspected plot to target a specific premises."
Ryan Jenkinson/Getty
Forensic officers in blue overalls were seen at a house in Rochdale, Greater Manchester, where one of the men was detained. Three of the arrests took place in the Greater Manchester area, one in London and one in Swindon.
Rochdale resident Kyle Warren told Britain's Sky News that he "heard a massive bang" and saw "20 or 30 police with guns" drag a man from a house in his neighborhood.
"We've seen a man getting pulled out from the back, basically got dragged down the side entry and thrown into all the bushes and then handcuffed," he said.
Video shot by bystanders and obtained by CBS News' partner network BBC News showed armed police removing a man from a home in Rochdale, while another clip showed a man being dragged through a street in Swindon with his hands bound and covered in plastic bags. The BBC said military personnel took part in the Rochdale arrests.
An eyewitness in Swindon told the BBC they saw six men go into a cafe and order coffee and donuts before following a suspect who had been inside out of the business, where they "jumped on him."
Commander Dominic Murphy, head of the Met's Counter Terrorism Command, said police were still working to establish a motive, "as well as to identify whether there may be any further risk to the public."
Police forensic officers search a house in Rochdale, England, May 4, 2025.
Ryan Jenkinson/Getty
Separately, three other Iranian men, aged 39, 44 and 55, were arrested in London on suspicion of a national security offense as part of an unrelated investigation, police said.
Home Secretary Yvette Cooper said "these were two major operations that reflect some of the biggest counter-state threat and counterterrorism operations that we have seen in recent years."
Britain's domestic intelligence service, MI5, has warned of a growing threat from attackers linked to Tehran. Cooper said "the ongoing investigation is immensely important" to determine whether the arrests were connected to the Iranian state.
"This reflects the complexity of the kinds of challenges to our national security that we continue to face," said Cooper.
MI5 chief Ken McCallum said in October that his agents and police had tackled 20 "potentially lethal" plots backed by Iran since 2022, most aimed at Iranians in the U.K. who oppose the country's authorities.
He said at the time that there was a risk "of an increase in, or broadening of, Iranian state aggression in the U.K." if conflicts in the Middle East deepened.
In March 2024, Pouria Zeraati, a presenter at a Farsi-language television station critical of the Iranian government, was stabbed in the leg outside his home in London. Two men were later arrested in Romania and charged over the attack.
The U.K.'s official terror threat level stands at "substantial," the middle of a five-point scale, meaning an attack is likely.
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