The Britain-based Syrian Observatory for Human Rights (SOHR) said on Friday that at least 30 civilians including 13 children were killed in air strikes in eastern Syria.
It was not clear if the air strikes were carried out by Russian warplanes in Deir Ezzor Province, which is mostly controlled by the DAESH terrorist group, the monitor said.
The monitor also reported that eight women were among those killed in the strikes on Tabiyyah Jazeera, around 20 kilometers east of Deir Ezzor city, the provincial capital.
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.
It says that dozens of people were wounded and that the death toll is expected to rise.
The air stikes came as Assad regime forces fight with DAESH terrorists 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 killed by DAESH terrorists.
DAESH controls most of the province, in whicg the regime has clung onto parts of the provincial capital and nearby military airport.
But with its multi-front assault, DAESH now controls 60 percent of the city and has tightened a siege of the roughly 200,000 people still inside it.
The Russian Federation which supports Syrian regime leader Bashar al Assad began an air strike campaign it claimed was directed against DAESH last September.
However, Russia mostly conducts air strikes against Western-backed opposition groups in which hundreds of civilians have been killed.
SOHR reported on Wednesday that at least 3,000 people, including more than 1,000 civilians, have been killed in Russian air strikes since September 30.
The human rights watchdog said at least 893 DAESH members were also among those killed in the air strikes.
More than 250,000 people have died as a result of the ongoing conflict in Syria, which will soon enter its sixth year, turning the country into the world’s largest source of refugees and displaced persons, according to the UN.