Syrian government troops advanced overnight against the Islamic State group in the country's north and centre, drawing closer to the key battleground of Deir Ezzor, a monitor said.
As the Islamic State group closes in on Syria's Deir Ezzor, residents said they are terrified of falling victim to the mass killings for which the jihadists have become infamous.
Syrian government forces clashed with Islamic State group fighters for a fourth day on Tuesday in an eastern city where a jihadist assault has left more than 100 dead, a monitor said.
Syrian and Russian warplanes have launched a wave of air strikes in northern Syria, killing dozens in areas held by a rebel alliance battling to take control of second city Aleppo.
At least 29 civilians were killed in air strikes suspected to have been carried by Russian warplanes on a village in eastern Syria on Saturday, a monitoring group said.
At least 35 Syrian soldiers and pro-regime militiamen were killed Saturday in a multi-front attack by the Islamic State group on the eastern city of Deir Ezzor, a monitor said.