IS counter-attacks kill dozens of US-backed fighters in east Syria

The Britain-based Syrian Observatory for Human Rights monitor said IS launched "three separate assaults" on Saturday.

The monitoring group said the counter-attacks targeted the villages of Al-Bahra and Gharanij and an area close to the Al-Tanak oilfield, which is commercially active but is also a military position of the Kurdish-led SDF. 

SDF spokesman Mustefa Bali confirmed "a series of attacks" led by IS in these three locations and said fighting had taken place all day, with the Kurdish-led ground forces receiving air support from the US-led anti-IS coalition.

The fighting on Saturday alone killed 29 SDF fighters, taking its total losses over the last two days to at least 47, said Observatory head Rami Abdel Rahman. 

Thirty-nine IS jihadists have been killed - some in the ground clashes, others in air strikes - over the same period, the Observatory said.  

IS confirmed in a statement on Telegram that it had launched attacks near Al-Bahra and Gharanij. 

Earlier, the Observatory said IS had broken out of its holdout on Friday to attack Al-Bahra, where SDF fighters and coalition advisers are based.

"IS launched a broad attack on the village of Al-Bahra next to its holdout, taking advantage of the fog," Abdel Rahman said.

The monitor said coalition raids have also killed 17 civilians, including five children, in the IS-held pocket since Friday.

The anti-IS alliance has repeatedly denied previous reports of civilians killed in its air strikes, and said it does its utmost to avoid hitting non-combatants.

IS overran large swathes of Syria and neighbouring Iraq in 2014, proclaiming a "caliphate" in land it controlled but has lost most of it to offensives by multiple forces in both countries.

In Syria, the jihadists are largely confined to the pocket in Deir az-Zour, but they also have a presence in the vast Badia desert that stretches across the country to the Iraqi border.

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