Four people have been arrested as part of a counter-terrorism investigation relating to Iran, the Metropolitan Police has said.

Police arrested one Iranian and three dual British-Iranian nationals on suspicion of assisting a foreign intelligence service.

The investigation relates to the suspected surveillance of locations and individuals linked to Jewish communities in London, the Met said.

Searches remain ongoing in Watford, Barnet, and an address in Wembley.

A 40-year-old and a 55-year-old were arrested at addresses in Barnet, a 52-year-old in Watford and a 22-year-old in Harrow.

Six other men aged 29, 39, 42, 49 and two aged 20, were arrested at the same location in Harrow on suspicion of assisting an offender.

All 10 men have been taken into custody.

Commander Helen Flanagan, head of Counter Terrorism Policing London, said the arrests, which took place around 01:00 GMT, are part of "a long-running investigation and part of our ongoing work to disrupt malign activity where we suspect it".

"We understand the public may be concerned, in particular the Jewish community, and as always, I would ask them to remain vigilant and if they see or hear anything that concerns them, then to contact us," she added.

The arrests and search activity is being led by Counter Terrorism Policing London.

The four men were detained under the National Security Act, which was introduced in 2023 to modernise counter spying laws, combating foreign interference.

After Iran launched retaliatory strikes following the US-Israel attack at the weekend, Prime Minister Sir Keir Starmer condemned Iran's actions against "partners across the region".

He said British planes were "in the sky" in the Middle East "to protect our people, our interests and our allies".

"Even in the United Kingdom, the Iranian regime poses a direct threat to dissidents and to the Jewish community," Sir Keir added.

"Over the last year alone, they have backed more than 20 potentially lethal attacks on UK soil.

"So it is clear they must never be allowed to develop a nuclear weapon."

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