A US airstrike in the Syria has killed 25 civilians, over half of whom were women and children, the Syrian Observatory for Human Rights revealed today.

The attack took place on Friday, south of the country’s eastern province of Deir Ez-Zor, in the settlement of Dahra Alouni close to Al-Shaafa region. The strike allegedly hit a school in the town which was housing displaced civilians. Dozens were injured as the four houses next to the school were also destroyed by the impact.

When asked about the report, coalition spokesman Colonel Ryan Dillon said: “We take all allegations seriously and as we always do, we will put it into our civilian casualty assessment and we will publish the results of those on a monthly basis.”

This was the second attack committed by the Syrian Democratic Forces (SDF) in a week, after at least 15 people were injured last Monday in the town of Al-Bahrah. Last month, three women were also killed after a hospital in Hajin city was struck.

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The SDF, made primarily of Kurdish forces, has been battling Daesh forces in Deir Ez-Zor since late 2014 when the group had held most of the province, except for one large pocket where Syrian regime troops and 93,000 civilians had been fighting for three years.

Despite being driven out of large parts of the province, Daesh militants still control pockets of the area with many of its fighters being deployed on the eastern side.

Continued fighting in the region has sent thousands of civilians fleeing for their lives, some forced into the desert as they try to escape the violence. International NGO Save the Children estimates that some 350,000 people have fled the oil-rich province, half of whom are children.

Earlier this month, the SDF clashed with Syrian pro-government forces, leaving over 100 dead; the US said the move was in response to an unprovoked attack near the Euphrates River.

However, such incidents have been sporadic and US-backed SDF and the pro-Syrian forces have largely avoided direct confrontation while fighting the common enemy Daesh. Moscow and Washington maintain contacts in eastern Syria to prevent an unexpected confrontation between forces they support.

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