Twelve people, among them children, were killed on Sunday in an air strike on a high school in a city of northern Syria held by the opposition, the Syrian Observatory for Human Rights said.
"The Syrian air force bombed a technical high school in the city of Raqa, killing 12 people, most of them children under 18, and wounding many other people, some of them seriously," the Observatory said, according to Agence France-Presse.
Raqa is on the Euphrates valley 160 kilometers east of the main northern city of Aleppo, it is the only provincial capital entirely in the hands of opposition, largely al-Qaeda loyalists of the Islamic State of Iraq and the Levant (ISIS).
The air strike came after rebels launched an overnight attack on army positions in Nasseriya al-Qalamun, north of Damascus, killing at least 19 soldiers and wounding 60, the Observatory said.
“There were also losses in the ranks of the rebels, who succeeded in capturing several positions,” AFP quoted the Observatory as saying.