Russian jets carried out on Sunday a series of strikes against ISIS targets in Syria's desert Badia.
It launched over 30 strikes in the al-Rasafah area in Raqqa's western countryside, the Palmyra desert, al-Sukhna in Homs' eastern countryside, and the desert in Jabal al-Bishri in southwestern Deir Ezzor.
No human casualties were reported.
Meanwhile, the Syrian Observatory for Human Rights said ISIS has executed eight regime soldiers. Contact was lost with them in a desert region in Syria's east as they were headed to the al-Sukhna region on March 26.
The rights monitor did not say when they were killed.
Air raids against ISIS have been intensified after the terrorist group also increased its attacks in areas held by the government. It has also been carrying out more executions against its forces.
The Observatory confirmed the execution of 14 soldiers in the past 48 hours.
The Observatory has tallied the death of over 200 soldiers and pro-regime and Iran-backed fighters in various ambushes and attacks in the desert region stretching from Deir Ezzor, to Homs, Raqqa, Hama and Aleppo.
The attacks have also left 37 civilians dead. The government forces and their allies have killed 24 terrorists during that time.