The Turkish military says its warplanes have carried out 26 air strikes in northern Syria, killing up to 200 Kurdish fighters.
The army said the raids on the night of October 19 hit targets north of the city of Aleppo in areas recently captured by the Kurdish People's Protection Units (YPG) militia from the Islamic State group.
A senior Kurdish commander, Mahmoud Barkhadan, said no more than 10 fighters had died.
Syrian activists put the death toll at 11, and said the raids destroyed buildings used as YPG headquarters, meeting points, shelters, and weapons depots, as well as four vehicles.
The YPG is supported by the United States in its fight the IS group, but Turkey regards it as a terrorist organization linked to the outlawed Kurdistan Workers Party (PKK).