Women and children flee the Islamic State group's last pocket of territory in Syria in a truck / © AFP
US-backed forces pressed the battle to expel diehard jihadists from the last pocket of land under their control in eastern Syria on Tuesday after hundreds fled the holdout overnight.
Outside the "Baghouz pocket", the plains were littered with empty pistachio-coloured rocket shells, water bottles, clothes left behind, and rotting dog carcasses.
The extremist group declared a cross-border "caliphate" in Syria and Iraq in 2014, but various military campaigns have chipped it down to a fragment on the Iraqi border.
After a pause of more than a week to allow out civilians, the Syrian Democratic Forces (SDF) declared a last push to retake the pocket from the extremists on Saturday.
Aided by the warplanes and artillery of a US-led coalition, the Kurdish-led alliance has pressed into a patch of four square kilometres (one square mile).
SDF spokesman Mostefa Bali said heavy clashes were underway on Tuesday, after hundreds fled the battle zone during the night.
"A group of 600 civilians escaped from Baghouz at one in the morning and they are being searched now," he said.
Final offensive on last pocket of IS territory in Syria / © AFP
The Syrian Observatory for Human Rights said the new arrivals included women and children from France and Germany.
"Most of those who got out are foreigners," Observatory chief Rami Abdel Rahman said.
Coalition spokesperson Sean Ryan said US-backed forces were facing a fierce fightback.
"The progress is slow and methodical as the enemy is fully entrenched and IS fighters continue to conduct counter attacks," he said.
"The coalition continues to strike at IS targets whenever available."
- 'Six hours? In the cold?' -
On Monday, the Observatory said a coalition air strike killed 16 civilians.
An Italian journalist was also wounded as he covered the clashes and evacuated for treatment, a colleague said on Twitter.
The SDF launched the battle to expel IS from the eastern province of Deir Ezzor in September, slowly tightening the noose around the jihadists and their families since December.
Women and children fleeing from the last Islamic State group's tiny pocket in Syria sit in the back of a truck near Baghuz, eastern Syria / © AFP
In the past two months, more than 37,000 people, mostly wives and children of jihadist fighters, have fled into SDF-held areas, the Observatory says.
That figure includes some 3,400 suspected jihadists detained by the SDF, according to the Britain-based monitor, which relies on sources inside Syria for its information.
At a gathering point for new arrivals, dozens of men knelt on the ground.
Iraqi and Syrian women and children prepared to make the long journey north to a Kurdish-held camp for the displaced, after spending the night in tents.
A very thin child with dark circles around his eyes stumbled onto a truck, as other children screamed out for water and their mothers asked how long the drive would take.
"Six hours? In the cold?" shouted a wrinkled Iraqi woman.
Bali, the SDF spokesman, said on Saturday that up to 600 jihadists could still be left inside the pocket.
But the group's elusive leader Abu Bakr al-Baghdadi who proclaimed the "caliphate" in 2014 was likely not there, he said.
Inside the crumbling redoubt, Iraqis are now in charge, according to those fleeing it and the SDF, as a rift has emerged between them and non-Arabic speaking foreigners.
- 'Next week' -
At the height of their proto-state, Baghdadi's followers implemented their brutal implementation of Islamic law in an area the size of the United Kingdom.
But various offensives, including by the SDF and Russia-backed regime forces, have taken back all but a morsel of that territory near the village of Baghouz.
Once the "caliphate" is declared over, the fight will continue to tackle IS sleeper cells, the SDF and their allies have said.
Syrian Democratic Forces fighters stand guard as a convoy transports civilians fleeing the battered Islamic State group holdout of Baghouz / © AFP
The jihadist group retains a presence in eastern Syria's vast Badia desert and has continued to claim deadly attacks in SDF-held areas.
US President Donald Trump on Monday said the coalition may declare victory over IS in the region within days.
"Soon it will be announced, soon, maybe over the next week, maybe less," he told a rally in the US city of El Paso.
Trump shocked Washington's allies in December by announcing a pullout of all 2,000 US troops from war-torn Syria.
The decision has left Syria's Kurds scrambling for protection from Damascus against a long threatened attack by neighbouring Turkey.
After decades of marginalisation, the Kurds have largely stayed out of Syria's eight-year civil war, instead setting up their own semi-autonomous institutions in the northeast of the country.
Syria's war has killed more than 360,000 people and displaced millions since starting in 2011 with the repression of anti-government protests.