Fighting between the Syrian arm of al Qaeda and Western-backed rebels in northern Syria spread from Aleppo province into neighboring Idlib on Friday, the rebel group and an organization monitoring the civil war said.

Clashes began on Thursday when the al Qaeda Syria wing, the Nusra Front, seized positions from the Hazzm movement west of Aleppo, threatening one of the few remaining pockets of the non-jihadist insurgency.

A Hazzm official said by telephone clashes had spread to Idlib and that his group had retaken some areas previously controlled by Nusra. […]