Turkish jets carried out air strikes against Kurdish militants in the Gara region of northern Iraq on Friday and killed 19 militants, Turkish military sources said on Saturday.

The warplanes took off from an air base in Diyarbakir in response to threats that the Kurdistan Workers Party (PKK) militants were preparing an attack on military units at the border, the sources said.

Turkey frequently launches air attacks against PKK targets in the mountainous regions of northern Iraq near the Turkish border, where the Kurdish militant group's leadership has camps.

A ceasefire between the autonomy-seeking PKK and the state fell apart last year, triggering some of the worst violence in the three decades of the Kurdish insurgency.

More than 40,000 people, most of them Kurds, have been killed in Turkey's conflict with the PKK, which Ankara, the United States and European Union designate a terrorist organization.