The UK's battle against jihadists at home and abroad
21 August 2014 Last updated at 22:36 BST
There is growing concern about the numbers of young Britons heeding the call to join Islamic State forces in Iraq and Syria, many of whom have been radicalised online.
British authorities are working to tackle the threat posed by extremism, but how can the UK stem the flow of British jihadists to war zones and counter the threat they could pose if they return?
Mark Easton reports.