Clashes have broken out between Kurdish militants linked to the Democratic Union Party and al-Qaeda-linked groups in northern Syria near the border with Turkey.
Kurdish fighters, who are opposed to foreign interference in Syria, have been battling foreign-backed militants in the northern province of Raqa on Syria's border with Turkey.
Scores of al-Qaeda-linked militants have died over the past days in clashes with the Kurds.
On July 21, the Kurdish militants took control of a key checkpoint controlled by al-Qaeda-linked militants and seized light weapons, ammunition, a vehicle mounted with a heavy machine gun, and a mortar launcher.
On July 17, the Kurdish fighters also took control of the town of Ras al-Ain in the border province of Hasakah.
Tensions have been running high between Syria and Turkey, with Damascus accusing Ankara -- along with Saudi Arabia and Qatar -- of backing a deadly insurgency that has claimed the lives of many Syrians, including security and army personnel.