Five IS fighters were also killed
More than two dozen pro-government forces based in Syria's desert died in a surprise Islamic State group attack Tuesday, a day after the jihadists' ouster from the outskirts of Damascus, a monitor said.
"At least 26 regime soldiers and allied forces were killed in an IS attack at dawn today, against one of their posts in the Syrian Badiya," said the Syrian Observatory for Human Rights.
Among them were Iranian militiamen, said the Britain-based monitor.
The Badiya is a vast desert region stretching from central Syria to the eastern border with Iraq, where IS still holds small pockets.
Observatory chief Rami Abdel Rahman said the attack hit a small base east of Palmyra, the famed ancient city that Islamic State (IS) has overrun twice in Syria's war.
"It began with a car bomb targeting regime forces that set off clashes that are still ongoing," he said.
Five IS fighters were also killed.
"IS fighters launched their attack from a pocket they control in the Badiya, and which was the destination for IS fighters evacuated from southern Damascus on Sunday and Monday," Abdel Rahman added.
Syria's government on Monday seized a southern pocket of the capital from IS, announcing that the regime was back in full control of Damascus and its outskirts.
The Observatory, as well as a military source close to the regime, said the capture came after IS fighters were bussed out of the zone to desert territory.