Five Iranians suspected of plotting an attack on the Israeli embassy in London belong to a highly trained special operations unit, a former intelligence officer has suggested.
The group who were arrested on suspicion of preparing an act of terrorism allegedly belong to Unit 840, which carries out assassination and kidnapping missions for Tehran. It is also suspected that some of the operatives arrived in Britain disguised as migrants on small boats – a record 10,000 people have come over the English Channel in this way this year.
The men were arrested by UK special forces and counter-terrorism police on Sunday following what appears to have been an extensive surveillance operation by MI5, whose officers feared an attack was imminent at the embassy, in west London. Police have until Saturday to charge them or they must be released, unless further permission for detention is obtained.
However, Abbas Araghchi, Iran’s Foreign Minister, said his country “categorically rejects any involvement” in any alleged plot to conduct attacks in Britain. Iran also called on Britain to provide consular access to the detained Iranians.

The UK security services will almost certainly have been tipped off by Israel’s Mossad, which has widely penetrated the Iranian security services, said the former military intelligence officer, who has served in the Middle East.
The Unit 840 operatives were likely to have conducted an “abduction, shooting attack or bomb attack”. He said: “They will have been conducting surveillance, pattern of life, pattern of security, for months on the embassy.”
Migrant boat route
However, it is almost certain that the group, who are part of the IRGC’s Quds force, would have been watched by the security services, building up a picture of their tradecraft, plans and targeting, although it is unlikely to have picked them up crossing the English Channel.
The operatives could have “come in by an irregular route” with genuine migrants, said the security source, who spoke on condition of anonymity. “The small boats method of entry would chime with how this unit might enter the country.”
Detectives and intelligence officers will also be still investigating a large number of people from the Iranian diaspora, which numbers about 115,000 in Britain, who assisted in logistics and planning, said the source in a briefing to a handful of journalists.

Intelligence team arrests
Three other men were also arrested and charged under the National Security Act, in what police have said was an unrelated plot. It is understood that these men were from Iran’s Ministry of Intelligence, also known as Vevak, who are more conventionally trained than Unit 840 but are also close to the regime.
It was “shocking, disturbing but unsurprising” that the Iranians had targeted the embassy, given their long history of attacking Israeli diplomats, said Richard Pater, director of the Anglo-Israeli Bicom think tank.
“Their worldwide terror campaign complements their nefarious activity in the region and attests to the regime's extremist nature,” he added. “Their modus operandi remains the same, sadly, and shows little sign of changing.”
In 1992, 29 civilians were killed and 242 injured in a Hezbollah-Iran bombing at the Israeli embassy in Buenos Aires, Argentina.

Global operations
Unit 840 is a more recently established force attached to the Quds Force that conducts clandestine operations beyond Iran’s borders. It has been linked to a number of terrorist plots, assassination attempts and destabilising operations across the Middle East, Europe and Latin America.
In 2023 a plot by Unit 840 to kill two news anchors from the London-based Iran International news network was foiled by intelligence work. The outfit's work has also been hampered by a number of targeted assassinations of its commanders by Israeli security services.

Seeking soft targets
Security analysts in Israel told The National that Iran was seeking “soft targets” outside of the region after taking “quite a fair beating from Israel over the last six months”.
“One of their ways to seek retribution and revenge is to threaten Israeli assets around the world,” said one analyst. “It's about threatening soft Israeli targets where they don't necessarily feel vulnerable, and they can embarrass the British.”
One of those soft targets could be the upcoming Eurovision Song Contest in Switzerland, which has an Israeli entrant, after Israel’s National Security Council issued urgent advice to travellers. “International events of this type are a prime target for threats and attacks by various terrorist groups, given the potential for widespread media coverage in the event of a terrorist attack or violent protests during the event,” it stated, urging its citizens to be vigilant.
The threat of Iran-instigated violence in Britain has increased substantially since the October 7 attacks and Israeli operations in Gaza. In the last three years MI5 has disrupted more than 20 kidnap and assassination attempts against media outlets and dissidents that have been allegedly directed by Iran.