Britain's Defence Secretary has threatened to kill every single extremist who has left the UK for fight for ISIS

REUTERS/Toby Melville

• Gavin Williamson issued a direct threat to Britons still fighting for ISIS.
• He said "my view is a dead terrorist can't cause any harm to Britain."
• At least 800 people have left the UK to join ISIS in Iraq or Syria.
• Other terror experts have said they should instead be reintegrated.

Britain's new Defence Secretary has unequivocally threatened to kill Britons who leave the country to fight for ISIS.

Gavin Williamson told the Daily Mail on Wednesday evening:

"I do not believe that any terrorist, whether they come from this country or any other, should ever be allowed back into this country. [...]

"Quite simply my view is a dead terrorist can't cause any harm to Britain."

Williamson added that British fighters who flee the UK for other countries would be hunted down and prevented from returning home or finding havens in other countries. 

He said: "Make sure there is no safe space for them, that they can’t go to other countries preaching their hate, preaching their cult of death."

This could mean seizing their passports if they try to cross international borders, the Daily Mail said.

Williamson's threat was harsher than that of his predecessor, Michael Fallon, who resigned amid sexual misconduct allegations last month.

In October, Fallon said British nationals who have chosen to fight for ISIS in Iraq or Syria have made themselves "a legitimate target" and "run the risk every hour of every day of being on the wrong end of an RAF or a United States missile," according to The Telegraph.

Williamson's Wednesday remarks echoed those of Rory Stewart, an international development minister, who said last month: "The only way of dealing with them [foreign fighters] will be, in almost every case, to kill them."

Meanwhile, Max Hill QC, the UK's official anti-terror watchdog, has said that teenagers who joined ISIS "out of a sense of naivety" should be reintegrated into British society so as to avoid "losing a generation."

At least 800 Britons have gone to Syria and Iraq to fight for ISIS, according to the BBC. Sally Jones, a British woman who fled to join ISIS, was reportedly killed in a drone strike last month.

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