The Israeli embassy in London was the alleged target of five Iranian men arrested on suspicion of preparing an act of terrorism, the BBC understands.

Police have not yet confirmed that the embassy in Kensington was the suspected target, as first reported by the Times, citing operational reasons. But the BBC understands the report is accurate.

Commander Dominic Murphy, head of the Metropolitan Police counter-terrorism command, said it was a “fast-moving” investigation and there were “significant operational reasons” why the force could not provide further details.

Iran “categorically rejects” any involvement, said the Iranian foreign minister, Seyed Abbas Araghchi, on the social media site X.

He added his country was ready to assist with the investigation.

The men – two aged 29, a 40-year-old, a 24-year-old and another aged 46 – were arrested on Saturday over an alleged plan to target “a specific premises”, the Met said.

The men were arrested in Swindon, west London, Stockport, Rochdale and Manchester.

Four of the men are continuing to be questioned under the Terrorism Act. The fifth man, who was detained under the Police and Criminal Evidence Act (PACE), was released on bail until a date in May.

Officers carried out searches at a number of addresses in Greater Manchester, London and Swindon as part of the investigation.

Footage showed armed officers taking a man from a house in Rochdale, while another man was dragged through the street in Swindon with plastic bags over his arms.

Commander Murphy said “as soon as possible we will look to share further details and in the meantime we would ask the public to remain vigilant.”

Commissioner for countering extremism Robin Simcox said it was quite unusual for an embassy to be targeted in the UK.

“I think the scale of Iranian-backed activity in this country is probably underestimated,” he told BBC Radio 4’s Today programme.

“We are increasingly aware of the hard power side of things but Iran also looks to spread its influence in the UK via religious institutes it controls, television channels, charities, educational institutes, online disinformation campaigns – all organisations which share Tehran’s aims and objectives.

“It is not always very visible. Iranian actives I think are a bit more subversive and a bit subtler – they are probably a bit more strategic in their targeting.”

Speaking in the Commons on Tuesday, Home Office minister Dan Jarvis said hundreds of officers were carrying out forensic investigations at different sites across the country.

He said the arrests were “some of the largest counter-state threats and counter-terrorism actions that we have seen in recent times”.

The five arrests took place on the same day as three other Iranian men were arrested as part of a separate counter-terrorism investigation.

They were arrested under section 27 of the National Security Act 2023, which authorises police to detain those suspected of “foreign power threat activity”.

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