Syrian army troops have killed 175 rebels in an ambush south of Damascus as part of a government effort to secure the capital.
The dawn attack by president Bashar Assad's forces in the opposition-held area of eastern Ghouta is likely to push rebel groups against his rule further away from Damascus. The capital's suburbs have been opposition strongholds since March 2011, when the revolt against the ruling family began.
If confirmed, it would be one of the deadliest attacks by government forces against rebels in the area.
A field commander in the eastern Ghouta area said most rebels killed in the assault near Oteibah lake southeast of Damascus belonged to the al-Qaida-linked Nusra Front rebel group. The report said several of those killed were foreign fighters who came to Syria from Saudi Arabia, Chechnya and Qatar to fight.
The official Sana news agency said the army's operation dealt "a smashing blow to terrorists", a term Syrian state media uses for rebels.
Sana posted several photographs on its website showing dozens of bodies of men lying in a dirt track of an open field, some wearing soldiers' uniforms, but most wearing civilian clothes.
The British-based Syrian Observatory for Human Rights also reported the killings, saying that 70 rebels were killed in the assault.
The Observatory, which has been documenting Syria's nearly three-year-old conflict by relying on activists' reports on the ground, says the number of those killed is likely to rise because 89 rebels have been reported missing.
In a live broadcast from the area, Lebanon-based television station Al-Mayadeen also showed dozens of bodies scattered along an unpaved road.
An army colonel told Al-Mayadeen that his troops acted on intelligence and the rebels lost "more than 150 men" in the assault. Syrian army tanks and armoured personnel carriers were seen in the broadcast as were soldiers patrolling on foot.
Syria's conflict started as largely peaceful protests against Assad's rule in March 2011. It has gradually turned into a civil war that has taken increasingly sectarian overtones, pitting mostly Sunni Muslim rebels against Assad's government that is dominated by Alawites, a sect in Shiite Islam.
More than 140,000 people have been killed, according to activists.