IRAN-backed terror cells could be deployed to launch deadly attacks in the UK, according to intelligence sources quoted last night.

As tensions escalate over the seizure of a British oil tanker, spy chiefs believe Iran may give the green light to its hidden proxy fighters if the crisis deepens.

10 Iranian Revolutionary Guard commandos preparing to seize a British oil tanker on Friday. UK spy chiefs say Iran could launch terror attacks in Britain Credit: Reuters

10 Iranian President Rouhani. Tehran could give the green light to proxy terrorists to unleash attacks on British soil if open warfare breaks out Credit: AP:Associated Press

Should open warfare erupt, MI5 and MI6 think Iran could call upon its network of terrorist sleeper cells to carry out atrocities, The Telegraph reported.

Iran seized the British oil tanker Stena Impero on Friday - the latest escalation in three months of spiralling confrontation with Britain and the West.

Tehran directly linked the hijacking of the vessel - which was captured in dramatic footage - with Britain's role in detaining a tanker carrying Iranian oil earlier this month.

The terror cells are run by radicals linked to Hizbollah - the Lebanese militant group backed by Iran.

Iran has Hizbollah operatives in position to carry out a terrorist attack in the event of a conflict. That is the nature of the domestic threat Iran poses to the UK Intelligence source

An intelligence source said: "Iran uses proxies and they have control of a network of individuals linked to Hizbollah.

“Iran has Hizbollah operatives in position to carry out a terrorist attack in the event of a conflict.

"That is the nature of the domestic threat Iran poses to the UK.”

British counter-terror police disrupted a major cell in 2015 that was caught stockpiling tonnes of deadly explosive materials at businesses on the outskirts of London.

Security services feel these raids - led by M15 and the Metropolitan Police - severely disrupted Iran’s terrorist activities in the UK.

But Iran's network of sleeper cells are believed to be widespread throughout both Britain and the rest of Europe.



'ORGANISED TERRORISM'

The 2015 operation - which was only uncovered last month - unearthed what was described as “proper organised terrorism” that would have done “a lot of damage”.

Security chiefs see Iran as ranking behind only Russia and China as the country posing the greatest threat to Britain’s national security.

Tehran has previously been accused of a series of cyber attacks in the UK - including the hacking of MPs and peers in 2017.

An attack on the Post Office, local government networks and banks at the end of 2018 was also suspected to have been ordered by Tehran.

10

The Government is preparing further responses to the seizure of the Stena Impero - which was captured in Omani waters as it sailed through the Strait of Hormuz on Friday.

The British Astute-class nuclear-powered submarine, believed to be at sea already, is expected to head to the region within days.

HMS Duncan, a Type 45 air-defence destroyer, was also heading towards the Gulf to assist the Navy’s only warship in the area, the Type 23 Duke class frigate HMS Montrose.

In one of her last duties as Prime Minister, Theresa May will chair a meeting of the Government's emergency committee Cobra on Monday.

She is expected to receive updates from ministers and officials on the situation and discuss security of shipping in the flash-point region.

Foreign Secretary Jeremy Hunt will also update MPs on the situation on Monday afternoon.

Reports suggest that ministers are considering freezing Iranian regime assets as part of its retaliation.

10

On Sunday, audio footage emerged between Iranian authorities and Royal Navy frigate HMS Montrose moments before the Stena Impero was seized.

In the radio recording, the Iranian vessel can be heard saying: "If you obey, you will be safe.

"Alter your course immediately. I want to inspect the ship for security reasons."

HMS Montrose replied: "You must not impair, impede, obstruct or hamper the passage of the Stena Impero.

"Please confirm that you are not intending to violate international law by attempting to board."

Reports from Tehran state the 23 crew members on board the Stena Impero - none of whom are British - are safe and well.

IRAN CRISIS: The key points:

Iran’s Revolutionary Guard stormed UK-flagged oil tanker the Stena Impero in the Strait of Hormuz on Friday

Royal Navy frigate HMS Montrose steamed to its aid but arrived late

Jeremy Hunt said there would be “serious consequences” and promised a "robust response"

Iran repeated demands for Gibraltar to release an Iranian tanker seized while smuggling oil to Syria

The Royal Navy released footage of a failed attempt by Iran to seize BP tanker British Heritage

Dramatic audio revealed the Royal Navy ordered Iranian forces not to board the Stena Impero moments before hijack

Ministers were yesterday forced to deny that the Conservative leadership race and Brexit concerns were partly to blame for the the tanker being seized.

HMS Montrose was an hour away from the Impero when it was captured.

Chancellor Philip Hammond's parliamentary aide Huw Merriman told BBC Radio 4 that the Government "have dropped the ball" over the situation.

Mr Merriman said: "Just to show that I'm not the puppet of Philip Hammond or Jeremy Hunt, I take the view that we have dropped the ball here.

"We did not put in place a chain where we asked all of our vessels to leave at a certain time under convoy.

"So it was hardly a surprise when one of ours got taken."

ROYAL NAVY 'TOO SMALL'

Mr Hammond insisted the Government had been "very much engaged with both the Americans and our European partners".

And Defence Minister Tobias Ellwood said the UK had vessels going through 100 nautical miles of waterway every day in the region.

He added: "It is impossible simply to escort each individual vessel."

But he warned the Royal Navy is too small to protect British ships from Iran.

Mr Ellwood called for more money to be invested in the Royal Navy if Britain wants to continue to play a role on the international stage.

PATROLLING WATERS

HMS Montrose is patrolling the Persian Gulf to protect shipping.

Earlier this month the frigate intercepted Iranian patrol boats surrounding another UK-flagged tanker.

A second oil tanker, the Liberian-flagged Mesdar - which is managed by Norbulk Shipping UK - veered off course towards the Iranian coast after it was boarded by armed guards at about 5.30pm on Friday.

Communication with the ship was later re-established and the crew were unharmed.

The tanker was reportedly allowed to resume navigation.

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Tensions continue to mount in the world's most important oil shipping lane after tighter US sanctions took effect at the start of May.

Washington imposed the sanctions after President Donald Trump pulled out of the Iran nuclear deal.

It had provided Iran access to world trade in return for curbs on its nuclear programme - curbs that have since been reversed.

10 Dramatic footage captured Iranian troops seizing the Stena Impero as it passed through the Strait of Hormuz on Friday Credit: EPA

10 Masked Iranian commandos abseiled from a helicopter as they stormed the vessel Credit: AFP or licensors

10 The Stena Impero was seized on Friday - the latest in a series of provocations between Iran and the West Credit: EPA

10 An Iranian gunboat escorts the oil tanker into Iran's waters on Friday Credit: Reuters

10 State TV showed the Iranian flag being hoisted up the Stena Impero in a taunt against Britain Credit: PressTV

10 Royal Navy frigate HMS Montrose was 10 minutes too late to intervene in the seizure of the oil tanker Credit: Reuters

Footage shows Iranian flag hoisted on seized British oil tanker Stena Impero

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