The homegrown jihadists fighting for ISIS: One in four foreigners who have signed up to Islamic State is British - and half of them are ALREADY back in the UK

Questions have been raised as to whether enough is being done to stem the flow of fighters as only 23 passports have been seized this year to prevent them travelling to the war zone. The Government says there are around 500 British while a further 250 are thought to have already returned to the UK where the police and security services are attempting to watch them.  The murder of James Foley apparently by 'John' - one of a gang of British jihadis known as 'The Beatles' - has raised fears the killing fields of Syria and Iraq are dominated by extremist Britons. MailOnline has profiled the most high profile jihadists known to have fled for Syria and Iraq.