Kurdish fighters were mounting a desperate defence of the northeastern Syrian border town of Ras al-Ain on Tuesday, battling Turkish forces seeking to set up a buffer zone in the region.
Here are the main events in a day of fierce clashes and mounting global concern:
- On the ground -
- The Kurds use a dense network of tunnels, berms and trenches to combat a fierce offensive by pro-Turkey troops on Ras al-Ain, despite Ankara's repeated claims to have captured the area. The Syrian Democratic Forces, the de-facto army of the Kurdish administration in northeast Syria, "launched a major counterattack overnight," the Syrian Observatory for Human Rights says.
- The Turkish defence ministry says two Turkish soldiers have been killed in shelling from the Manbij region in clashes with Kurdish forces. It does not give the precise location, but says that "15 terrorists" were killed when the Turkish army returned fire.
- Russia says Syrian government forces have taken full control of Manbij, as the US-led coalition confirms it has left the northern city.
- The clashes force international aid organisations to flee northeast Syria, halting all their operations.
- Turkish President Recep Tayyip Erdogan says the operation, now in its seventh day, would not stop until "our objectives have been achieved".
- Diplomatic front -
- After brokering a cooperation deal between Syria and the Kurds allowing regime forces to deploy in Kurdish-controlled areas, Russia says it will not allow clashes between Syrian and Turkish forces.
- Moscow also reveals its forces are patrolling "the lines of contact" on the border areas between the two forces, saying "cooperation has been organised" with the Turks.
- Diplomats say the UN Security Council will convene on Wednesday to discuss Turkey's military incursion in northeast Syria at the request of European nations.
- The UN warns that reports of summary executions of civilians in the northeast by pro-Turkish fighters may amount to "war crimes".
- Britain suspends military exports to Turkey as it carries out a review of arms sales to its NATO ally. Foreign Secretary Dominic Raab warns "no further export licences to Turkey for items which might be used in military operations in Syria" until the review is over.
- France's top diplomat Jean-Yves Le Drian unveils plans to fly to Iraq to discuss the situation in northern Syria, and in particular "the security" in the camps where the foreign jihadist prisoners are held. He also calls for an urgent meeting of the US-led anti-IS coalition.
- Qatar defends its ally Turkey saying Ankara had acted against an "imminent threat".