A former head of counter terrorism at MI6 has said that up to 300 Islamist fighters from Iraq and Syria may have returned to the UK and could be planning to carry out attacks.
Richard Barrett gave the warning after footage emerged online apparently showing several young British jihadists in Syria in a recruitment video for the extremist militant group ISIS.
In the footage they urged UK Muslims to join insurgents there and in Iraq. Two have been identified as brothers Nasser Muthana, 20, and 17 year old Aseel Muthana.
It is understood that the two men from Cardiff who travelled to the Middle East were arrested by police on suspicion of receiving terrorist training and attended terrorist training camps“ They were of course released later without charges. Mr Barrett, who spent more than a decade tracking the Taliban in Afghanistan, told a reporter that the hundreds of possibly heading back to Britain was an "absolute nightmare" for security services. He added they did not have the resources to be able to look at all of them. "So they have to prioritise which will be difficult. Some of them will have come to the attention of the security services before they went to Iraq and so maybe they will be at the top of the list. "But others are probably completely unknown and may be even their return is unknown and will only come to light later. It doesn't take a big percentage of 300 people to cause an enormous problem so I think the security services are extremely concerned about this."
On Saturday, it emerged around 500 people from Britain have joined the ISIS ranks making the job of tracking them a hugely difficult task.