"The number of victims of a blast at the filling station in the industrial area in eastern Azaz increased to… five people, while 21 more were injured," the source said.
The cause of the explosion is yet to be ascertained, the source indicated. According to preliminary information, the blast might have been caused by an explosive-laden vehicle.
Azaz is situated in Syria's northwestern province of Aleppo, which is currently controlled by the militants of Turkey-backed Free Syrian Army opposition group.