Kurds 'may be releasing' IS prisoners in Syria to get US involved: Trump

President Donald Trump suggested Monday that Kurdish fighters may be releasing imprisoned Islamic State group jihadists to bait the United States into remaining involved in northeastern Syria.

The Pentagon said Sunday 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 last week 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." Kurdish authorities said Sunday that 800 IS family members being held in a camp at Ain Issa in northern Syria had fled due to Turkish bombing.

Turkey denied Monday that its offensive had allowed Islamic State prisoners to break out of detention camps, charging Monday that Kurdish militants had instead deliberately "emptied" a prison.

Turkey is in the sixth day of its offensive in Syria against the YPG, which it sees as "terrorists" but which were a crucial ally for the United States and western powers against IS.

The United States and its partners have condemned the Turkish invasion but their threats of sanctions have failed to stop it.