On March 15, the war entered its eighth year.
Air strikes have killed at least 11 civilians and wounded dozens more in an ISIL-held central Syrian village in Hama province, according to a monitor.
Rami Abdel Rahman, the head of the Syrian Observatory for Human Rights, said the raids targeted a livestock market in the village of Oqayrabat that is held by the Islamic State of Iraq and the Levant (ISIL) group.
“They are probably Russian air strikes,” he said.
Al Jazeera could not independently confirm the report.
The British-based Syrian Observatory, which relies on a network of sources inside Syria for its information, says it determines whose planes carry out raids according to type, location, flight patterns and munitions used.
Abdel Rahman said the raids on the village were part of “new military operations by the Syrian regime and its Russian ally targeting jihadist positions in Hama province”.
Syrian and Russian jets on Saturday were heavily bombing ISIL fighters north and east of Palmyra, which has changed hands several times in Syria’s nearly six-year war.
Oqayrabat lies northwest of Palmyra, the ancient desert city that was recaptured by Russian-backed government forces from ISIL on Wednesday.
The road between the two had often been used by ISIL to travel between the provinces of Hama and Homs, where Palmyra lies.
Also on Saturday, the Syrian state news agency SANA reported that the government recaptured eight villages from ISIL in northeast parts of Aleppo province supported by the Russian air strikes.
According to the Syrian Observatory, the target of the operation was ISIL-held Khafsah, the main station pumping water into Aleppo.
Residents of Aleppo, Syria’s second city, have been without mains water for 47 days since ISIL cut the supply.
The fighting over the past week has sparked an exodus of “more than 30,000 civilians, most of them women and children”, the Syrian Observatory said on Saturday.
Most of the displaced went to areas around Manbij, in Aleppo province, held by the US-backed Syrian Democratic Forces (SDF) – an alliance of Kurdish and Arab fighters who are also fighting ISIL.
An AFP correspondent in Manbij saw dozens of families speeding towards the relative safety of the city on motorcycles and in small buses and cars.
Many looked exhausted as they lined up at a checkpoint manned by the Manbij Military Council, the SDF unit that controls the town, to be searched and receive permission to enter.
Ibrahim al-Quftan, co-chairman of Manbij’s civil administration, told AFP that as many as 40,000 displaced had arrived in recent days.
“The numbers of displaced people here are still rising because of the clashes between the Syrian regime and Daesh [ISIL],” Quftan said.
“These people are suffering very difficult circumstances.”
Manbij already plays host to “tens of thousands of displaced people that fled previous clashes in the area and are living in difficult circumstances”, said the observatory’s Abdel Rahman.
“This will make it difficult [for local authorities] to welcome a new wave of displaced people, given their inability to tend to their pressing needs.”
Also on Saturday, Turkey said a MiG-23 fighter jet, probably belonging to the Syrian air force, had crashed on the Syrian side of the border. There was no pilot in the wreckage.
“The MiG-23, believed to have been owned by the Syrian regime, crashed on the Syrian side of the border,” Binali Yildirim, Turkey’s prime minister, said.
“The pilot may have bailed out and come down on either side … A search-and-rescue operation is under way.
“It’s not clear why the plane crashed. It may be due to weather conditions.”