The number of Britons who have left the country to join Daesh (ISIL) and similar extremist groups in the Middle East is on the rise, according to a new report.
An estimated 850 Britons have gone to fight with Daesh or other terrorist groups in Syria and Iraq, according to the British daily The Guardian.
In January, the British government put the figure at about 800. The Guardian estimates that about 100 of them have been killed.
Of the remaining 750 Britons, roughly half have returned to the UK and half remain in Syria and Iraq.
Hundreds of others have been stopped before leaving the UK or during passage through Turkey, which is the main access route. Most of them are thought to have been under the age of 30.
Of the estimated 850 Britons who have joined Daesh, more than 50 are women, according to UK police.
Many of the foreign recruits to ISIL are thought to be treated as disposable, based on the testimony of militants who have fled the Takfiri group. They say the core of Daesh is made up of experienced, extreme, militants from the Middle East and former members of the Iraqi army.
Some of the Britons with computer or social media skills are given high-profile propaganda jobs.
Syria and Iraq has been gripped by foreign-backed militancy since 2011.
The ISIL terrorists have been committing vicious crimes against all ethnic and religious communities in Iraq and Syria, including Shias, Sunnis, Kurds, Christians and others.
In 2014, the US and some of its allies started conducting airstrikes inside Syria against Daesh terrorists, many of whom were initially trained by the CIA to fight against the Syrian government.