Images posted on social media showed intensive air raids against targets in the Kabani mountains and in the vicinity of the town of Saryah, south of Idlib.
Local activists confirmed the neutralization of dozens of radicals and the destruction of ammunition warehouses and drone launch pads.
At least 65 terrorists were killed while four observation points and an equal number of weapons depots were hit, according to officials, who were quoted by local media.
They added that the 11th Tank Division sent units of the 67th Assault Brigade and 135th Artillery Regiment to the front lines.
The joint Syrian-Russian operations are carried out in response to recent attacks by the extremists, who stepped up their armed actions from Idlib against residential areas under government control, and launched four drone attacks that killed four civilians.
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