Syrian government warplanes on Wednesday struck a series of targets in a northern city that is a stronghold of an al-Qaeda splinter group, killing at least 12 people, opposition activists said.
The airstrikes on Raqqa, a city of some 500,00 that has been under control of the Islamic State of Iraq and the Levant for more than a year, appear to be part of an intensified Syrian government campaign against the militant faction that has become a major fighting force in neighboring Iraq in recent weeks.
The Britain-based Syrian Observatory for Human Rights said the jets struck targets around the provincial capital of Raqqa, including a market and the headquarters of the Islamic State.
Another activist group, the Syria-based Local Coordination Committees, also reported the strikes, saying that five people were killed in a single strike that targeted the Islamic State building.
An opposition activist in Raqqa reported at least seven airstrikes on Wednesday on the city. The activist, who goes by the name of Abu Noor, said in an interview over Skype that 13 bodies of civilians have been identified. He said the death toll will likely rise due to a large number of wounded.
An array of rebel groups fighting to overthrow Syrian President Bashar Assad captured Raqqa in March 2013. The Islamic State eventually expelled the other opposition factions to take full control of the city, which is the only provincial capital to fall out of government hands.
In neighboring Iraq, Islamic state fighters have in recent days captured major cities and towns in the north and west. They have also seized border crossings with Syria and Jordan from the Shiite-led government in Baghdad.
Also Wednesday, Syrian aircraft carried out a series of airstrikes in the eastern, oil-rich province of Deir el-Zour near the border with Iraq, the Observatory said.
Islamic state fighters have been battling rival rebel groups for months in the oil-rich province. There were no immediate reports of reports of casualties.
In Deir el-Zour, at least two airstrikes struck Muhassan, a town along the Euphrates River near Iraq that has been daily pounded by warplanes since the Islamic State fighters captured it last week.