As many as 2,000 Britons are fighting alongside extremist militants in Syria and Iraq, according to The Telegraph.

As many as 2,000 Britons are fighting alongside extremist militants in Syria and Iraq, according to The Telegraph.

Officials had suggested that the number of British 'jihadists' within the ranks of ISIL and other terrorist groups was about 500.

There are growing fears that the British authorities remain unable to detect extremists leaving UK ports on their way to terrorist training camps.