US-backed forces 'retake Islamic State hub in east Syria'

Kurdish-dominated forces backed by US coalition air strikes have retaken full control of a key Islamic State hub in eastern Syria, according to a UK-based activist group.

The Syrian Democratic Forces (SDF) secured Hajin, the largest settlement in what is the last pocket of territory controlled by IS, the Syrian Observatory for Human Rights said on Friday.

"After a week of heavy fighting and air strikes, the SDF were able to kick IS out of Hajin," said Observatory head Rami Abdel Rahman.

The operation was completed at dawn, he said, a day after SDF forces fanned out across the large village in the Euphrates valley, the AFP news agency reported.

SDF officials could not immediately be reached for comment.

SDF commander-in-chief Mazloum Kobani told the Reuters news agency on Thursday that at least 5,000 IS fighters remain holed up in the pocket of territory including Hajin and that they had decided to fight to the death.

This includes some 2,000 foreign fighters, mostly Arabs and Europeans along with their families.

Kobani also said it was possible that IS leader Abu Bakr al-Baghdadi was in eastern Syria, but the SDF could not be sure because he often disappears.

'Hajin pocket'

Hajin is the last big town held by IS in its remaining pocket of territory east of the Euphrates River near the border with Iraq.

The SDF, spearheaded by the Kurdish YPG militia, has been battling to finish off IS for several months in the area.

The last IS fighters were confined to a network of tunnels and the edges of Hajin, which lies in the eastern province of Deir Ezzor, about 30km from Iraq.

The area held by IS is sometimes referred to as the "Hajin pocket," the last rump of a once-sprawling "caliphate" the group proclaimed in 2014 over swathes of Syria and Iraq.

According to Abdel Rahman, a total of 17,000 fighters from the Kurdish-Arab SDF alliance are involved in the operation to flush IS out of its last bastion.

Islamic State fighters still control some desert terrain west of the river in territory that is otherwise controlled by the Damascus government and its allies.