A Turkish drone strike in northern Syria killed four Syrian Kurdish fighters on Thursday, the second such attack in recent days, a Kurdish official and a war monitor said.
The Kurdish Asayish security forces said that "a drone attacked our forces" in the Ain Issa area in Raqa province, killing "four of our members". The statement condemned "Turkish attacks".
The Syrian Observatory for Human Rights war monitor confirmed the death toll in the "attack by a drone belonging to the Turkish military" in the north of Raqa province, according to AFP.
In recent months, Turkish President Recep Tayyip Erdogan has repeatedly vowed to launch a new offensive in Syria's north.
Ankara has launched successive military offensives in Syria. Most have targeted Kurdish fighters that Ankara links to a group waging a decades-long insurgency against it.
Turkey has increased the frequency of its drone strikes in Kurdish-controlled areas of Syria since a July 19 summit with Iran and Russia, according to Kurdish officials and the Britain-based Observatory, a monitoring group with a network of sources on the ground.
Four fighters including three commanders from the Kurdish-led Syrian Democratic Forces were killed on July 22 in a drone strike blamed on Turkey.
Russian and Iranian leaders urged Erdogan against launching a new Syrian offensive last week, but Turkey has insisted it does not need "permission".
Moscow and Tehran have supported the Syrian government in the decade-long conflict, while Turkey has backed various opposition groups.
