Fighting between an al-Qaeda-linked group and a loose alliance of more moderate and ultraconservative rebel brigades has killed nearly 500 people over the past week in northern Syria, an activist group said Friday.
The rebel-on-rebel violence that broke out a week ago has spread across four provinces in opposition-held parts of the north in what amounts to the most serious infighting among opponents of President Bashar Assad since the country's conflict began in March 2011. (AP)













