More than 40 people are reported to have been killed in clashes between Syrian Islamist rebels and Islamic State militants north of Damascus.
The Syrian Observatory for Human Rights said the fighting in the eastern Qalamoun mountains had left 30 rebels and 12 jihadists dead since Tuesday.
The area is important because it straddles rebel weapons supply routes.
IS had already cut off one route and aimed to take more to "suffocate" the rebels, the Syrian Observatory said.
The western part of the Qalamoun mountains, which borders Lebanon, is mostly controlled by the government and fighters from the allied Lebanese Shia Islamist movement, Hezbollah.
Meanwhile, 13 civilians have been killed in the north-western province of Idlib.
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http://www.bbc.co.uk/news/world-middle-east-32418258
