At least 12 female ISIS militants were killed in the Syrian airstrikes on their headquarters in Raqqa.

The Syrian fighter jets, meantime, raided another ISIS headquarters in Raqqa, killing at least 22 Takfiri terrorists who were mostly from the Persian Gulf Arab states.

The second building was used by ISIS to prepare captive Izadi women to be sold at a later time.

In a relevant development last Saturday, the Russian and Syrian Air Forces, in coordinated operations, targeted the ISIS headquarters and positions in and around a strategic military airbase in the Northeastern province of Raqqa, inflicting heavy damage on the terrorists' logistical vehicles.

The ISIS military and logistic vehicles inside the Tabaqa military airport came under the heavy bombardments of the Syrian and Russian fighter jets, which ended in the destruction of the terrorists' vehicles in large scale.

The air attacks on Tabaqa forced the ISIS to face shortage on enough vehicles to supply its forces near Palmyra (Tadmur) with arms, medical equipment and foodstuff.

Battlefield sources said Last week that Ansar Jeish al-Souri, the pro-Syrian Army battalions of Raqqa province's tribal forces, engaged in fierce clashes with the ISIS terrorists, and inflicted a heavy death toll on them.

"Due to heavy attacks of the tribal forces that can be found in every battlefront in the Northeastern province the number of the ISIS forces in the city of Raqqa has been significantly decreased and most of them have moved to al-Mayadeen region in Deir Ezzur to scape to Iraq," the sources said.

"The tribal forces and the Syrian army have advanced against the ISIS terrorists in Qabaqeb and al-Tim oil well and are pushing towards the city of Raqqa," they further added; FNA reported.

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