British police have arrested eight people, seven of whom are Iranian nationals, in two separate counter-terrorist operations over the weekend.

Commander Dominic Murphy, the head of counter terrorism at the Metropolitan Police, told Sky News one of the investigations involved a plot against a specific premises, which he declined to identify.

UK Home Secretary Yvette Cooper said: “These are major operations that have taken place and the ongoing investigation is immensely important, and of course it involves Iranian nationals in both investigations and we are supporting the police and the security agencies in the investigations that they are taking and the security assessments that they are doing.

“But this reflects the complexity of the kinds of challenges to our national security that we continue to face that we have set out and that is why protecting our national security including supporting these extremely professional operations and investigations remains our top priority.”

The Metropolitan Police said five men, including four Iranian nationals, were arrested across England on Saturday on suspicion of preparation of a terrorist act which would, “target a single premises.”

In a statement, the police said the four Iranians had been arrested under section 5 of the Terrorism Act 2006, and the fifth man—who nationality was “still being established”—was detained under the Police and Criminal Evidence Act.

The police said as part of the operation a 46-year-old man had been arrested in west London, a 29-year-old man had been detained in Swindon, in the west of England, two men, aged 29 and 40 had been arrested in Stockport and Rochdale, near Manchester.

The fifth man, whose age has not yet been ascertained, was also detained in the Manchester area.

In a separate statement, the force said three Iranian men were arrested in London on Saturday as part of a separate operation.

‘Foreign Power Threat Activity’

The Met said the men, aged 39, 44, and 55, were arrested and detained under section 27 of the National Security Act 2023, which allows the police to arrest anyone it, “reasonably suspects is, or has been, involved in foreign power threat activity.”

The statement said: “The investigation relates to a suspected plot to target a specific premises. Officers have been in contact with the affected site to make them aware and provide relevant advice and support, but for operational reasons, we are not able to provide further information at this time.”

Murphy said: “The investigation is still in its early stages and we are exploring various lines of enquiry to establish any potential motivation as well as to identify whether there may be any further risk to the public linked to this matter.”

Counter-terrorism officers spent Sunday searching several properties in London, Swindon, and the Manchester area.

Forensic officers in blue overalls were seen entering a house in Rochdale, Greater Manchester.

In a speech in October, the head of MI5, Ken McCallum, said: “Since the killing of Mahsa Amini in 2022 we’ve seen plot after plot here in the UK, at an unprecedented pace and scale.

“Since January 2022, with police partners, we have responded to 20 Iran-backed plots presenting potentially lethal threats to British citizens and UK residents.”

MI5—which comes under the Home Office—tackles domestic threats while MI6 is Britain’s foreign intelligence service.

In December 2023, a 31-year-old Austrian national, Magomed-Husejn Dovtaev, was convicted of spying on a London-based television channel, Iran International, which is critical of the Iranian government.

‘Hostile Reconnaisance’

The court heard Dovtaev visited the channel’s premises in Chiswick, west London, on Feb. 11, 2023 to carry out “hostile reconnaissance.”

He was later jailed for three years and six months for attempting to collect information useful for terrorism.

Iran International channel has been branded a terrorist organisation by the regime in Tehran after it covered massive protests in several Iranian cities in September 2022 following the death of Mahsa Amini, 22, who was detained by the morality police for not wearing a veil.

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.

In December 2024 the Crown Prosecution Service announced two men, Nandito Badea, 19, and George Stana, 23, had been arrested in Romania, and charged with wounding Zeraati, and wounding with intent to cause grievous bodily harm.

They have been extradited to the UK and face trial later this year.

The Associated Press, Reuters and PA Media contributed to this report.