'Dozens' of Islamic State fighters freed in Syria
James Jeffrey said the number of militants released was unknown, dismissing previous numbers that suggested a higher toll.
“I would say dozens at this point,” Jeffrey said at a congressional hearing in response to a question by Democratic Senator Chris Coons asking how many “hardened” IS fighters had been released.
The comments came after Kurdish authorities said 800 IS family members being held in a camp at Ain Al-Issa in northern Syria had fled due to Turkish bombing.
Turkey denied that its offensive had allowed IS prisoners to break out of detention camps, charging Kurdish militants had instead deliberately "emptied" a prison.
Earlier this month, the Pentagon said Trump had ordered the withdrawal of up to 1,000 troops from northern Syria - almost the entire ground force in the war-torn country - amid an intensifying Turkish assault on Kurdish forces.
Trump's decision to pull out of the area - clearing the way for the Turkish incursion - has been attacked at home as a betrayal of America's Kurdish allies, that risks triggering a resurgence of IS.
"Europe had a chance to get their ISIS prisoners, but didn't want the cost. 'Let the USA pay,' they said..." Trump tweeted, using an alternate acronym for the Islamic State group.
"Kurds may be releasing some to get us involved. Easily recaptured by Turkey or European Nations from where many came, but they should move quickly."
Ankara says the YPG is a "terrorist" offshoot of the PKK, which has been waging an insurgency inside Turkey since 1984. The PKK is blacklisted as a terrorist group by Ankara, the United States and the European Union.
The US and its partners have condemned the Turkish invasion but their threats of sanctions have failed to stop it.
The agreement cements Russia and Turkey's roles as the main foreign players in Syria after the US withdrawal.
The meeting saw Russia and Turkey agree to ensure Kurdish forces withdraw from areas close to Syria's border with Turkey and to launch joint patrols.
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