The Turkish military's General Staff said its warplanes targeted the outlawed Kurdistan Workers' Party (PKK) in areas near the border.
Turkey, a NATO member with European Union membership aspirations, has sought to end attacks from northern Iraq carried out by PKK rebels fighting for a Kurdish autonomy in Turkey's southeast.
On November 30, Turkey's government authorized the military to conduct a cross-border operation against Kurdish separatists in northern Iraq, following parliament's approval in mid-October.
Turkey has already deployed about 100,000 troops on the border with Iraq.
The PKK, labeled by the U.S., NATO and the EU as a terrorist organization, has been fighting for autonomy status in southeast Turkey for nearly 25 years. The conflict has so far claimed about 40,000 lives.