Police have been granted further time to question seven men arrested in two separate counter-terrorism investigations that both involved Iranian nationals.
Five men, who are all Iranian nationals, were arrested at locations across England on Saturday on suspicion of preparation of a terrorist act after a suspected plot “to target a single premises” was uncovered, the Metropolitan Police said on Sunday.
The force confirmed a further three Iranian men were arrested on Saturday as part of a separate operation.
Dominic Murphy, head of counter terrorism at the Met, said one was a terrorist plot to attack a specific premises, while the other was a national security issue.
Police are not treating the two cases as linked.
Home Secretary Yvette Cooper said on Sunday that the cases reflect the biggest counter state threat and counter terrorism operations in recent years.
The first four men were arrested on suspicion of preparation of a terrorist act, contrary to section 5 of the Terrorism Act 2006, and the fifth was detained under the Police and Criminal Evidence Act.
The first five arrested were a 29-year-old man in the Swindon area, a 46-year-old man in west London, a 29-year-old man in the Stockport area, a 40-year-old man in the Rochdale area and a 24-year-old man in the Manchester area.
Warrants of further detention were secured on Monday for four men, meaning they can be detained and questioned until Saturday, the Met said.
The 24-year-old man was detained under the Police and Criminal Evidence Act. He has been released on bail with conditions to a date in May, the force added.
As part of the investigation, officers are searching a number of addresses in the Greater Manchester, London and Swindon areas.
Mr Murphy said: “Our officers and staff are progressing what is a significant and highly complex investigation, and we still have searches and activity under way at multiple addresses across the country.
“We are working incredibly hard, with public safety at the forefront of our ongoing efforts.
“We believe that a specific premises was the target of this suspected plot and Counter Terrorism Policing officers remain in close contact with the affected premises.
“At this time, we will not be providing further information about the suspected target for reasons of operational security and public safety.
“I would like to ask people to support my officers in this and not to speculate or share information that has not been confirmed by Counter Terrorism Policing. We have clear and critical reasons not to provide more detail at this time.
“The investigation is still in its early stages and we are exploring various lines of inquiry to establish any potential motivation as well as to identify whether there may be any further risk to the public linked to this matter.
“As always, I would ask the public to remain vigilant and if they see or hear anything that concerns them, then to contact us.
“We are working closely with local officers in the areas where we made arrests on Saturday and I’d like to thank police colleagues around the country for their ongoing support.”
Another three Iranian men were arrested at three addresses in London as part of a separate counter-terrorism operation under section 27 of the National Security Act 2023.
Section 27 grants constables the power to arrest individuals without a warrant if they reasonably suspect them of being involved in “foreign power threat activity”.
Two men, aged 39 and 44, were arrested at separate addresses in north-west London and the third – a 55-year-old man – was held in west London.
All three were taken into custody and warrants of further detention have been obtained, meaning they can be detained until Saturday, the Met said.
