Demonstrators on the M4 highway in Idlib Province in northwest Syria, hoping to prevent Turkish and Russian patrols (AFP)

UPATE, 1215 GMT:

Protesters continue to challenge the Turkish-Russian agreement for joint patrols of the cross-Idlib M4 highway.

Two Turkish soldiers have been killed in Idlib Province in northwest Syria, the first fatalities among Ankara’s troops since a March 5 ceasefire halting a 10-month Russian-regime offensive and partitioning the area.

The Defense Ministry said a third soldier was wounded in an attack by “radical groups”.

The Ministry did not name the faction responsible. However, the pro-opposition Nedaa Call site said the attack was near the town of Muhambel, an area which has been controlled by the hardline jihadist group Huras al-Din.

The site said gunmen opened fire after detonating an improvised explosive device close to the cross-Idlib M4 highway.

Turkey and Russia began military patrols in a 12-km (7.5-mile) wide corridor along the M4 on March 15, ten days after Turkish President Recep Tayyip Erdoğan and Russian counterpart Vladimir Putin agreed the ceasefire.

The deal allowed pro-Assad forces to occupy about half of Idlib, following the Russian-regime offensive that began last April. The attacks killed almost 2,000 civilians and displaced more than a million deeper into opposition territory near the Turkish border.

Demonstrators have gathered for a weeks on the M4, preventing the Turkish patrols. Ankara’s troops have been trying to repair trenches and remove earthen berms on the highway.