The Anadolu Agency quoted Jabal al-Islam Commander Zahir Abu Usama, as saying that "Russia is "intensely attacking Idlib".
"In order to alleviate these attacks, we have launched an operation around Turkmen Mountain in regime-controlled Sarraf town and around the region," he added.
The Commander further said that they have seized Assad regime controlled villages of Villa and Kapikaya in Sarraf.
Reportedly, opposition's sudden attacks have also killed several soldier's.
After the opposition's operation, Russian and regime warplanes attacked Turkmen Mountain, local sources said.
In May last year, Russia, Iran and Turkey signed an agreement to set up de-escalation centres in Syria. De-escalation zones include the Idlib province, some parts of Latakia, Hama and Aleppo provinces, Homs, Eastern Ghouta, Daraa and al-Quneitra provinces in southern Syria.
Syria has been embroiled in a civil war since 2011.
Protesters have for long been demanding the resignation of Assad over his autocratic rule. (ANI)