Hundreds of radicalised fighters invade UK and it is 'IMPOSSIBLE' to track them #TheElitePartyInJuly #Entertain9jar via @myentertain9jar

HUNDREDS of radicalised jihadists who went to Syria and Iraq could have returned to the UK and it is IMPOSSIBLE to track them all, an expert warned today.

A terror expert has warned hundreds of jihadists who went to Iraq and Syria could be back in the UK[IG]

The former head of counter-terrorism at MI6 Richard Barrett said it was "inevitable" the extremists fighters will pose a threat to the UK.

The terror expert, who spent more than a decade tracking the Taliban, said police do not have the resources to find all of the jihadists on our shores.

Speaking to the Independent on Sunday, Mr Barrett warned: "If you imagine what it would cost to really look at 300 people in depth, clearly it would be completely impossible to do that, probably impossible even at a third of that number.

"With this whole business in Syria, although there is no linear projection from foreign fighters to domestic terrorists, it's inevitable that a number will fall into this category."

Mr Barrett also co-authored a report out this month which states more than 12,000 foreign fighters have gone to Syria since the war began.

The study claims it is "likely to be an incubator for a new generation of terrorists".

An ex MI6 terror boss said police do not have the resources to find all of the jihadists in the UK [IG]

If you imagine what it would cost to really look at 300 people in depth, clearly it would be completely impossible to do that

Terror expert Richard Barrett

The comments come as the founder of anti-extremist think tank Quilliam warned that the UK faces a backlash from terror group Isis.

Maajid Nawaz claimed that Isis have eclipsed Al Qaeda as the "new standard for global jihad" and the west should be fearful of attacks.

Writing in the MailOnline, Mr Nawaz said: "There are already thousands of foreign fighters who have joined ISIS.

"Western countries must prepare for an ISIS backlash as these fighters return home.

"These battle-hardened fighters require little consistent logic to attack us.

"It would be naive in the extreme to assume otherwise.

"The sad fact is we are woefully unprepared."

The news come after a recruitment video for terror group Isis featuring three Britons went online [IG]

The extremists have already seized several key Iraqi cities, including the country's second largest city, Mosul and are advancing towards Baghdad.

On Friday a recruitment video for Isis was posted online showing three Britons in Syria urging their countrymen to "answer the call and fight for Allah".

One of those Britons who appeared in the chilling clip was 20-year-old student Nasser Muthana.

His 57-year-old father Ahmed said he broke down in tears when he saw the video and it was the first time he found out his son was in Syria.

The student had left his family home in February saying he was going on a trip to Shrewsbury and was later joined by his younger brother Aseel, 17.

The elder Mr Muthana said: "I feel very sad. It's devastating.

"Not only shocking - devastating. I wish they would come back, that's all I would say to them - come back.

"I think they are in the wrong hands. I don't know why they would have done this."