Southern Syria rebels set collision course with al Qaeda
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Western-backed fighters in southwestern Syria, the one part of the country where they are strong, have spoken out this week against al Qaeda, a sign of friction that could lead to new fighting among opponents of President Bashar al-Assad.
Four years into a civil war, most of Syria's territory is held either by the government of President Bashar al-Assad or by two main jihadist groups: Islamic State mainly in the east, and al Qaeda's Syria branch, the Nusra Front, in the northwest.
Western and Arab countries oppose both Assad and the jihadists. Washington, which is leading an international campaign of air strikes against Islamic State, says its strategy is to support what it describes as "moderate" rebels.
Although such Western-backed fighters control comparatively little territory, an alliance known as the Southern Front has an important foothold near the borders with Jordan and Israel. It has seized a border crossing and a government-held town in recent weeks after weathering a government offensive.
