BEIRUT (Reuters) - At least 56 civilians were killed on Tuesday in air strikes north of the besieged Islamic State-held city of Manbij in northern Syria, near the border with Turkey, a monitoring group said.
Residents believed the strikes were carried out by U.S.-led coalition planes, the British-based Syrian Observatory for Human Rights said. It said the dead included 11 children, and dozens more people were wounded.
On Monday 21 people were killed in raids also believed to be by U.S.-led coalition planes on Manbij's northern Hazawneh quarter.
The U.S.-backed Syria Democratic Forces (SDF), an alliance of Kurdish and Arab fighters, launched an offensive at the end of May to seize the last territory held by Islamic State on the frontier with Turkey.
But progress into Manbij city has been slow. The militants have deployed snipers, planted mines and prevented civilians from leaving, hampering efforts to bomb the city without causing heavy casualties, Kurdish sources have said.
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