Russia's Defense Ministry says its military aircraft have hit positions of the Al-Qaeda-linked Al-Nusra Front near the Syrian city of Aleppo.
As a result, the ministry said, an attempted offensive by the Islamist militants was thwarted.
According to the ministry, hundreds of militants controlled by the Al-Nusra Front have attacked Kurdish fighters in Aleppo, killing 18 civilians and 11 of the fighters.
The Syrian Army and its allies have launched an offensive to retake a town near Aleppo that was captured days earlier by Nusra militants, activists said earlier on April 6.
Syrian activists said government forces were aiming to retake the village of Tel al-Ais, which overlooks the Damascus-Aleppo highway.
The developments come as the Al-Nusra Front confirmed on April 6 the death of Abu Firas al-Souri, a senior figure in the group, in a U.S. air strike in the northern province of Idlib on April 3.