Thousands of ISIS fanatics will be released from prison the day after US troops pull out of Syria, it is claimed.
The news comes after US president Donald Trump announced a withdrawal of US armed forces from the war-torn country to the dismay of some western Allies.
Kurdish forces helping to fight the militants have reportedly agreed to release 1,100 Islamic State fighters and 2,080 relatives as a response to the American withdrawl.
The threat of returning ISIS militants will seriously concern counter-terror police in Europe and in the United States.
A US government source speaking to the New York Times confirmed the rumours, and said: “If they are released, it’s a real disaster and major threat to Europe.”
The British Foreign Office said in a statement that “much remains to be done and we must not lose sight of the threat they pose.”
The decision is said to be a stark contrast to conventional US policy, which has come as a surprise to allies.
Donald Trump announced the surprise withdrawal on Wednesday
Many believe a premature withdrawal from Syria would inevitably lead to a resurgence of the the extremist group.
Even senior Republican figures have expressed contempt against the motion.
Republican Senator Lindsey Graham, one of Mr Trump’s most avid supporters, called the withdrawal decision a "huge Obama-like mistake”.
The decision has concerned America’s Kurdish allies in Syria
Military intervention from the US, including targeted air strikes, have helped push Islamic State militants back from areas controlled by the Syrian Democratic Forces, a predominantly Kurdish group.
Kurdish fighters are concerned that the withdrawal from Syria could prompt an invasion by Turkish which sees Syrian Democratic Forces as a threat.
“The White House’s decision to withdraw from northern and eastern Syria will negatively affect the campaign against terrorism and will give terrorism and its supporters the political and military momentum to restore ISIS’ power again,” the group said.
The news comes after US president Donald Trump announced a withdrawal of US armed forces
Earlier today, ISIS threatened drone attacks against the west in a chilling new poster.
The warning comes after a drone near Gatwick Airport caused travel chaos and hundreds of flight cancellations.
The image, which has circulated online, shows a photoshopped image of a drone carrying an unknown consignment as it ominously flies over New York.
A tag-line reads: "Sender: The Islamic State."
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