JOIN USTurkey said on Monday it had "neutralised" 101 Syrian regime soldiers following a bombardment which killed five Turkish soldiers in northwestern Syria's Idlib region, the last major rebel bastion.
The Turkish defence ministry said its troops were pushing on with bombardments on Syrian positions in the area on Monday evening.
Under a deal with Russia, Turkey has 12 observation posts in Idlib as a way to avert an offensive by Syrian government forces trying to retake it from rebels, but Syrian troops have been advancing despite Ankara's warnings.
"According to our sources, 101 regime troops were neutralised, three tanks and two cannons were destroyed and a helicopter was hit," the Turkish ministry statement said.
Earlier Monday, five Turkish soldiers died in Syrian regime artillery fire in Idlib.
The barrage also wounded five soldiers in the violence-plagued northwest, prompting the Turkish military to respond by "destroying targets", the defence ministry added.
The exchange was the second in eight days and took place in the area of Taftanaz, which was recently reinforced by Turkey, said the Britain-based Syrian Observatory for Human Rights.
Monday's incident comes a week after earlier regime shelling killed eight Turkish soldiers, prompting a deadly response by the Turkish army.
The clashes are further straining relations between Damascus and Ankara, while also increasing tension between Russia and Turkey -- the conflict's chief foreign protagonists.
Turkey has beefed up its Idlib positions in recent days by sending at least 350 vehicles with commandos backed by armoured vehicles.
But the regime supported by Moscow has intensified an assault against the last major rebel bastion, home to an estimated three million, for more than two months.