On Saturday, the Turkish General Staff said that at least five Turkish servicemen were killed and one tank destroyed by Kurdish militants in Syria's northern district of Afrin.
"We are investigating the circumstances around death of five of our soldiers, we are probing the weapons of what country hit the tank… Regardless of what country gave the terrorists those weapons — it works together with them," Erdogan told a press conference.
On January 20, the Turkish Armed Forces launched Operation Olive Branch against the Kurdish forces in Afrin, an area controlled by the US-backed YPG, which are considered by Ankara to be affiliates of the Kurdistan Workers' Party (PKK), designated as a terrorist organization in Turkey and several other countries. The operation has been conducted jointly with the Free Syrian Army forces.
Damascus has firmly condemned the operation as an assault on Syria's sovereignty. Moscow, in turn, has urged all the parties to exercise restraint and called for respect for Syria's territorial integrity.