Humanitarian groups in northeastern Syria are scrambling to provide aid to hundreds of thousands of people as rapidly shifting battle lines make it increasingly difficult to reach them.
Nearly all foreign aid workers have been evacuated because of security concerns, and there are fears that local staff could face reprisals, either at the hands of Turkish-led forces pushing in from the north or Syrian troops fanning out across territory held by the embattled Kurds.
The front lines are being rapidly redrawn as more than 160,000 people flee the fighting, including many who were displaced by earlier battles in Syria's eight-year civil war.
The offensive has created a new refugee crisis in a region where some 1.6 million people already rely on humanitarian aid.
Before the offensive, a camp in the northern town of Ein Eissa held an estimated 12,000 displaced people, including around 1,000 wives and widows of Islamic State fighters and their children.
But rioting broke out as Turkish-led forces closed in over the weekend, leading to the escape of hundreds of Islamic State supporters.
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Sonia Khush, the Syria response director at Save the Children, which was operating in the camp, now says it is "nearly empty," with most of the residents having fled further south and the IS supporters melting away.
She said the aid group can no longer access its office in Ein Eissa, and that most of its local staff have themselves been displaced.
"We have to leave as the battle lines change," she said.
Turkish troops and allied Syrian fighters invaded northern Syria a week ago after US President Donald Trump pulled back US troops who had partnered with Syrian Kurdish forces in the costly five-year war against the Islamic State group.
Turkey views the Kurdish fighters as terrorists because of their links to the decades-long insurgency in its southeast.
Abandoned by their US allies, the Kurds turned to Syrian President Bashar Assad and Russia for protection, and over the past two days Syrian and Russian forces have moved into several towns and villages as the US has pulled its remaining troops from the region.
So far, most of the displacement has been within northern Syria, but hundreds of refugees have crossed into Iraq in the past week, mostly through unofficial border points.
On Wednesday, a first group of 890 people were bused to a camp in Bardarash, in northern Iraq's semi-autonomous Kurdish region, which up until two years ago housed displaced people from the Iraqi city of Mosul.
"Where can go except here?" said Omar Boobe Hose, a refugee from the northern Syrian town of Ras al-Ayn, which has seen heavy fighting.
"We can't go to Turkey, because they are our enemy, and the other side is also our enemy, the Syrian (government) side. Where can we go? We have only here. There are no other places for Kurds."
"Given the numerous groups fighting on different sides of the conflict, MSF can no longer guarantee the safety of our Syrian and international staff."
The International Rescue Committee also said it has suspended its health operations in the northeast because of "hostilities and uncertainty."
The warring parties "need to guarantee that aid workers and civilians will not be targeted."