Nearly 700 killed in Syria rebel infighting

Syria's civil war within a civil war

 Nearly 700 people have been killed in nine days of fierce clashes between an al Qaeda affiliate and other Islamist and rebel groups, activists said Sunday.

Forces from the al Qaeda-affiliated Islamic State of Iraq and Syria have increasingly come into conflict with Free Syrian Army fighters and other hard-line factions opposing the Syrian regime, while ISIS attempts to impose its strict form of Islamic Sharia law on areas coming under its control in northern Syria.

In the last nine days, 697 people have been killed in the fighting, activists said.

The victims include 351 combatants from the Islamist and non-Islamist rebel battalions, 246 ISIS fighters, and 100 civilians, the Britain-based Syrian Observatory for Human Rights said.

The activist group said the deaths took place between January 3 and January 12. 

Among the 100 civilians killed in the clashes, 21 were executed by ISIS in the children's hospital in Qadi Askar in the northern rebel stronghold of Aleppo, the group said.

CNN cannot independently verify daily death tolls, but the United Nations has said more than 100,000 people have been killed in Syria since 2011. 

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