Freezing temperatures kill scores of Syrian children fleeing fighting

The cold has killed close to 30 children in two months among the civilians who have been fleeing the last extremist pocket in eastern Syria, the United Nations said on Thursday.

The World Health Organization said it was extremely concerned by the conditions for those who make it to al-Hol, where lies the main camp for people displaced by the fighting against the Islamic State group.

"At least 29 children and newborns are reported to have died over the past eight weeks, mainly from hypothermia, while travelling to the camp or shortly after arrival," the WHO said in a statement.

It said about "23,000 people, mainly women and children fleeing hostilities in rural areas of neighbouring Deir az-Zour," had reached the camp over that period.

Kurdish and local Arab tribes backed by a US-led coalition are battling the last shreds of the IS "caliphate" near the town of Hajin in the Euphrates River valley.

"Many of them have walked or travelled in open trucks for several days and nights in the bitterly cold winter weather," the WHO said.

It explained the displaced were often delayed for hours in the open countryside while SDF forces screened them to look for extremists trying to blend in.

The UN's health agency said the situation in al-Hol required urgent and unhindered humanitarian access.

"The situation in the camp is now critical. Its population has tripled in size (from 10,000 to almost 33,000 people) in less than two months," it said.