An official with the US-backed force fighting ISIS in eastern Syria says some 500 people, including fighters, have surrendered and evacuated the last area held by the extremists.

Ciyager, an official with the Kurdish-led Syrian Democratic Forces, says 200 more people are expected to evacuate the village of Baghouz.

Dozens of men, women and children climbed hills on foot and were later seen getting into small trucks after they were searched by SDF fighters.

An SDF spokeswoman said the offensive has slowed down but pressure is being kept up away from the evacuation corridor to prevent fighters from infiltrating or sabotaging the area.

She spoke on condition of anonymity because she was not authorised to speak to the press.

Earlier, US-backed Syrian fighters battling the militants in their last foothold in Syria said they had been forced to slow down their push because the extremists were using civilians as human shields.

But despite the slowing, Mustafa Bali, a spokesman for the Kurdish-led Syrian Democratic Forces, tweeted that the battle to retake ISIS-held Baghouz “is going to be over soon”.

SDF resumed its offensive to recapture Baghouz last Friday, after a two-week pause to allow for the evacuation of civilians.

Retaking the sliver of land would be a milestone in the devastating four-year campaign to end IS’ self-proclaimed Islamic caliphate that once straddled vast territory across Syria and Iraq.

Mr Bali said “we’re slowing down the offensive” due to a small number of civilians held as human shields.