
An underground network of Iranian sleeper cells poses an unlikely but credible threat to the UK, defense and security experts have told Metro.
The warning comes as British Iranians told us about how efforts to recruit them are commonplace when they visit Iran.
While highly unlikely, analysts say opponents of the Iranian regime and Britain’s Jewish community would be the most probable targets of hostile spying operations in the UK.
War between Israel and Iran erupted last week after Israel attacked Iranian cities and nuclear sites. In the early hours of Sunday, Donald Trump changed the face of the conflict by ordering US strikes on three of Iran’s key nuclear facilities at Fordow, Natanz and Esfahan.
A ceasefire between Israel and Iran has since been confirmed, denied, and confirmed again by senior figures in both administrations — though Iran’s supreme leader, Ayatollah Ali Khamenei, has yet to acknowledge it.
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Now, many are wondering what comes next, and whether it’s possible that the conflict could reach these shores.
Metro spoke to leading university academics and British-Iranians about reports that Iran could call on a network of ‘sleeper agents’ to target the West.
What are sleeper cells?
Sleeper agents are spies who are living seemingly normal lives until they are ordered to act. Together, they form a cell.
Two members of the Iranian community in London have said efforts to hire agents for underground activity are common.
Speaking on condition of anonymity, both said these efforts are often refused.
B, 34, said: ‘They interrogate you in semi-friendly conditions.
‘They take you somewhere and potentially hold your passport until you talk with them. Then they ask you to perform some tasks for Iran.
As to the purpose of sleeper cells, B said: ‘[The Iranian government] are quite interested in curbing any outside operations opposed to the regime which could have threats to the national security to Iran.’

Another man, who came to the UK after the Iranian revolution that overthrew the Shah in 1979, agreed: ‘They don’t treat you badly. They may threaten some people, but usually they look friendly.
‘There have been reports of people saying “No, I do not want to do that”.’
Security lecturer Dr Andreas Krieg pointed to the Basij, Iran’s paramilitary volunteer militia, as a way to get agents in the UK.
He said some of the million strong civilian network have come to the UK and have been ‘curated’ to spy on Iranian dissidents.
‘These people could be activated,’ the senior lecturer at the School of Security Studies at King’s College London added.
‘Iran always relies on proxy or surrogate networks. Sleeper cells are an instrumental part of that network strategy.’
Both experts were keen to stress there are not ‘hundreds’ of these spies in the UK, more like a ‘handful’.
What threat do Iranian sleeper cells pose to the UK?
Security experts and British-Iranians stressed that the risk of agents carrying out deadly attacks is low.
However, there are fears that Iranian dissidents in the UK will continue to be targeted.
B, who came to the UK when he was eight, stressed that Iran was more interested in spying on other Iranians. He described rumours of attacks on other groups as ‘scaremongering’.
He added: ‘The operations they would have are on tracking and surveillance of dissidents.
‘I do not think the UK is significant enough to warrant a strategic military attack, it is not worth the risk to reward.
‘Iranians do not like to be associated with these kind of terrorism.’

Prof Richards agreed that traditional attacks against Britons by sleeper cells are unlikely due to the preparedness of UK security services, but could not be ruled out.
Dr Krieg said he was most worried about attacks against the Jewish community in the UK.
The security expert told Metro: ‘One way Iran could choose to attack Israeli interests is by going after either Israelis overseas or by going after Jewish community centers and synagogues.
Dr Krieg said these would be lone wolf attacks, but stressed they are unlikely.
What triggers a sleeper cell?
Sleeper cells snap into action for a variety of reasons that can be ‘virtually impossible to spot’.
‘There’ll be some sort of command,’ Prof Julian Richards, the Director of Centre of Security and Intelligence at the University of Buckingham, explained.

‘Either directly from Iran, but more likely from agents who are here either temporarily or permanently, who know when and how to activate a particular sleeper cell.
‘It might be a message on the internet, or a coded message on a chat room or some sort of pre-arranged channel.’
How is the UK working to prevent sleeper cell attacks?
UK intelligence forces, such as MI5 and MI6 track suspected sleeper cell agents and watch for anything that indicates an attack is imminent.
Prof Richards and other experts said the UK’s counterterrorism preparedness makes the probability of an attack unlikely.
‘They’ll have been thinking over a number of years who might be targets of interest who might be people to watch,’ he added.

‘They’ll just be looking for a change in behaviour, such as a group of people moving from just talking to each other to actually discussing more specific plans of action.’
What other countries operate sleeper cells in the UK?
A host of states hostile to the UK are recruiting agents to spy on British soil. Among these, according to Prof Richards, are China, Russia and North Korea.
‘We know that those countries are very active in trying to recruit people covertly in this country,’ he said.
‘All will not necessarily want to carry out terrorist attacks but, in the case of China particularly, will be wanting to gather intelligence.’
In May, Commander Dominic Murphy, head of the Metropolitan Police Counter Terrorism unit, warned there is a growing threat of Russia using criminal proxies to spy on British soil.
It came after six Bulgarians were convicted of spying for the Kremlin in May.
The Great Yarmouth-based ring, dubbed ‘the Minions’, received orders from Russian intelligence services and conducted spying on an ‘industrial scale’.
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