An airstrike in eastern Syria on Friday killed at least 30 civilians, including 13 children, a monitoring group said.
It was unclear if the raids in Deir Ezzor province, mostly controlled by the Islamic State group, were carried out by Russian or regime warplanes, the Britain-based Syrian Observatory for Human Rights said.
The monitor said eight women were among those killed in the strikes on Tabiyyah Jazeera, around 20 km East of Deir Ezzor city, the provincial capital.
It added that dozens of people were wounded and the toll was expected to rise.
The monitor relies on a network of activists on the ground and distinguishes between Syrian, Russian and US-led coalition aircraft based on flight patterns, as well as the type of planes and ordnance used.
The strikes come as the regime battles IS jihadists who launched a major assault on Deir Ezzor city over the weekend.
The fighting there has killed at least 439 people since Saturday, according to the Observatory, including combatants who died in strikes or clashes, and civilians executed by IS.
While IS holds most of Deir Ezzor province, the regime has clung onto parts of the provincial capital, as well as the nearby military airport.
But with its multi-front assault, IS now controls 60 percent of the city, and has tightened a siege of the roughly 200,000 people still inside it.
Russia, a staunch ally of President Bashar al-Assad’s government, began an air campaign in support of Damascus last September. (AFP) RCB