Damascus: Eleven soldiers and two civilians were killed in a bus attack in northern Syria on Monday, according to a Syrian military statement.
The bus was ambushed at 6:30 am local time while en route from the northern province of Raqqa to the central province of Homs in an area called al-Jireh, said the statement.
A previous report said the dead were all soldiers. The military statement said three soldiers were wounded in the attack.
The statement called the attack an act of terrorism but did not name anyone responsible. There was no immediate claim of responsibility.
However, the war monitoring group Syrian Observatory for Human Rights said Islamic State (IS) militants were behind the bus attack, adding that at least 15 soldiers were killed in the attack in the desert area of Raqqa.
It said that the death toll could likely rise due to the number of critically wounded people.
Last week, the group said that five bodies of pro-government fighters were sent to hospital in the city of Palmyra after IS militants ambushed their car in the nearby desert region of Homs.
The IS has lost key areas in Syria but IS fighter cells have recently launched guerrilla warfare campaigns in the sprawling desert region of eastern Syria, resulting in frequent military and civilian casualties.