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. Commander Helen Flanagan, head of Counter Terrorism Policing London, said the arrests were part of "a long-running investigation and part of our ongoing work to disrupt malign activity where we suspect it".

She added : "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." In a statement, Home Secretary Shabana Mahmood sought to reassure the public that the UK's police and security services "are world leading" and would not hesitate to "take action to counter any threat to the UK". "They will continue to use the full range of tools and powers available to them to keep this country safe. They have the government's full support as they carry out their vital work."

Speaking to ITV's Good Morning Britain shortly after news broke of the arrests, Deputy Prime Minister David Lammy said: "Iran is the biggest state sponsor of terrorism globally and sadly, that is in effect in our own society as well. "Our intelligence services and counter-terrorism police have thwarted lots of action over the last few years," he added. He also praised the work of the security services and police. The Community Security Trust, a charity which seeks to protect Britain's Jewish community and monitors reports of antisemitism, thanked police in a statement and added: "Security is strong across the Jewish community." 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. (BBC)