Two people have been arrested on suspicion of assisting Iran's intelligence service, the Metropolitan Police said.
A 42-year-old woman and a 60-year-old man were detained at addresses in London by officers from Counter Terrorism Policing London, as part of an investigation into suspected National Security Act (NSA) offences.
It follows searches of addresses in north-west London on 24 June, with a third property in the area also searched on 9 September.
Both were held on suspicion of an offence under section 3 of the NSA, 2023 - assisting a foreign intelligence service.
The suspects were taken to a London police station, and were subsequently released on bail with strict conditions until a date in late October.
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Police said the investigation was not connected to any of the incidents or attacks earlier this year that have been targeted at various venues and buildings linked to Jewish and Iranian communities across London.
Commander Helen Flanagan, head of Counter Terrorism Policing London said: "We know that news of these arrests will come as a concern to some members of the public, but I want to stress that we do not believe there to be any imminent threat to the wider public in connection with this matter.
"We've seen a marked increase in the tempo of our work linked to national security and state threats over the past year and this investigation is a continuation of that.
"As we've shown here, if we suspect any activity could threaten the safety of the UK or the public, then we will not hesitate to take action."
She added: "I would also like to remind the public that the overall terrorism threat level is at severe, so we continue to ask for everyone's support through being vigilant, and if you see or hear anything that doesn't look right, then please, trust your instincts, and report it to us."
(c) Sky News 2026: Two arrested in London on suspicion of assisting Iran's intelligence service
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