Fighters of the Syria Democratic Forces prepare to fire a mortar shell towards positions held by Islamic State fighters in northern province of Raqqa, Syria

“The Syrian army backed by Russian air strikes has advanced toward Islamic State-held Raqqa province in a new offensive”, a group monitoring the war said, nearing a region where U.S.-backed militias have also attacked the jihadist group.

Heavy Russian air strikes hit IS-held territory in eastern areas of Hama province near the provincial boundary with Raqqa on Friday, where the army had advanced some 12 km (7 miles), according to the Syrian Observatory for Human Rights.

The army was around 12 km from the Raqqa provincial boundary.

U.S.-backed militias including the Kurdish YPG are pressing a separate, multi-pronged attack against IS in Raqqa province and neighboring Aleppo province, which escalated this week with a push toward the city of Manbij near the Turkish border.

A pro-Damascus Lebanese newspaper said that “the Syrian army was entering the race for Raqqa with its new offensive”.

A Syrian military source, however, said that “reports of an attack targeting Raqqa was expected, and that both Raqqa and Deir al-Zor, which are also in the hands of IS insurgents, were possible targets of army operations”.

The army announced on Thursday a new operation backed by Russian air strikes in the Athriya area of eastern Hama province close to the provincial border with Raqqa.

The State media said that “the army had made territorial gains and inflicted heavy casualties”.

“There is a progress from Athriya on two fronts but the coming direction is not fixed,” the military source said.