The airstrikes hit positions of the IS in and around the Tabaqa airbase, which was one of the latest military positions that fell in the hands of the IS militants, who declared the entire province of Raqqa as their de facto capital, Xinhua news agency reported citing according to state-run SANA.
The IS, previously known as the Islamic State in Iraq and the Levant (ISIL), proclaimed the establishment of an "Islamic caliphate" straddling Syria and Iraq, and changed its name into the "Islamic State".
The group led by Abu Bakr al-Baghdadi, who commands tens of thousands of fighters, said its goal was to establish an Islamic state in Iraq and Syria to fight the Shia-led government of Iraq and that of Syrian President Bashar al-Assad, whose top ranks are from the Alawite minority, an offshoot of Shia Islam.
Syria has been gripped by deadly conflict since March 2011. Over 200,000 people have reportedly been killed and millions displaced due to the violence.