A car bomb in Syria's western Hama province killed 34 and wounded more than 50, Syria's state news agency SANA said on Friday, blaming the attack on rebels fighting forces loyal to President Bashar al-Assad.
It was not immediately clear if the attack was in any way related to the militant Islamic State of Iraq and the Levant (ISIL), which is very active in Syria and has seized vast tracts of territory across the border in Iraq.
Nusra Front, which is linked to al Qaeda and has been fighting rival group ISIL, is thought to have been behind several bomb attacks in Hama in recent months.
The Syrian Observatory for Human Rights, an anti-Assad monitoring group, said 38 were killed and more than 40 wounded in the blast which took place in Hurra, an Alawite village close to the city of Hama. Assad is from Syria's Alawite sect, an offshoot of Shi'ite Islam.
It said a suicide bomber in a truck had detonated himself, killing mainly civilians, including women and children.
It said there were overnight clashes between government forces and Islamist fighters in the province, as well as bombings by the Syrian army.
SANA described the car bomb as a "terrorist" attack, wording it uses to refer to rebel fighters.
The agency said the Syrian army had also carried out a campaign to eliminate "terrorists" in a number of villages in the Homs province to the south of Hama.
Syria's conflict began in March 2011 as peaceful protests but has turned into civil war, killing at least 160,000 people.
Rebels have been joined by hardline Islamists, some of them linked to al Qaeda, who have become increasingly powerful among opposition forces.
In the northern city of Aleppo, Syrian air forces dropped two barrel bombs on the outskirts of the Ashrafiyeh neighbourhood, the Observatory said, adding that there were no details on casualties.