Undercover SAS troops deployed on the streets of Britain to guard Christmas shoppers and New Year’s Eve revellers from ISIS terror attacks

ARMED undercover SAS anti-terror troops are set to police Britain's High Streets over the festive period in a bid to thwart ISIS attacks, it has been claimed. 

The elite troopers have been deployed amid fears over Islamic attacks and have been given a 'shoot to kill' order if they believe civilians are at risk.

They will operate undercover in major British cities including London, Birmingham, Manchester and Leeds.

Intelligence sources believe British-born members of ISIS returning from Iraq and Syria are determined to carry out assaults.

A source told the : “MI5 believes hundreds of Britons who fought with Islamic State in Syria and Iraq will be returning to the UK in the next few months.

“Many will want to take revenge on the UK for attacks launched by the RAF and the special forces on Islamic State strongholds in Syria and Iraq.

“These people are very determined, battle-hardened terrorists, who are more than ready to die for their cause.

"They represent a significant threat to the UK.”

The SAS troopers will work closely with MI5 intelligence officers to identify terror suspects, while army bomb disposal experts will also be on hand to deal with suspicious devices.

Expert snipers trained to kill suicide bombers moving through crowds will also be on hand to boost security.

Earlier this month the chief of MI6 Alex Younger revealed that MI6 has disrupted 12 major terrorist plots in Britain since June 2013.

The spymaster also revealed fresh details on how ISIS is targeting the UK from deep inside Syria, branding the threat’s scale as “unprecedented”.

And last week six terror suspects were arrested in a series of dawn raids as properties were searched in Derby, Burton and London.

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