Britain will feel the repercussions of Syria and the rise of Islamic extremism within its own borders for "many years" to come, a top counter-terrorism expert has said.
Cressida Dick, the Metropolitan Police's assistant commissioner who recently failed in her bid to become PSNI Chief Constable, warned that Britain would feel long-term consequences of the conflict.
She was speaking as Sunni militants captured two border crossings, one with Jordan and another with Syria, as they press on with their offensive in one of Iraq's most restive regions.
Iraq officials said the militants yesterday captured the Turaibil crossing with Jordan and the al-Walid crossing with Syria after Iraqi forces pulled out.
Ms Dick said Islamic extremism represented a terrorist threat to the UK, and that young British Muslims who had travelled to war-torn Syria to fight might commit violence when they return.
It is estimated that around 500 Britons have travelled to Syria and Iraq.
Ms Dick told BBC Radio 4: "I'm afraid I believe that we will be living with the consequences of Syria – from a terrorist point of view, let alone the world, geopolitical consequences – for many, many, many years to come."
Her warning came after footage emerged online showing several young British jihadists in Syria in an Isis recruitment video in which they urged UK Muslims to join insurgents there and in Iraq.