Shafaq News/ Turkey's airforces bombarded strongholds of the anti-Ankara Kurdistan Workers Party (PKK) on the Matin mountain chain in the governorate of Duhok earlier today, Sunday.

Eyewitnesses told Shafaq News Agency that a squadron of at least ten Turkish helicopters struck mount Kurzar in the Amadiyah district, northern Duhok.

There are no information on whether the attack resulted in casualties until the moment.

Turkey is taking its decades-old conflict with Kurdish militants deep into the Kurdistan region and northern Iraq, establishing military bases and deploying armed military drones against the PKK fighters in their mountain strongholds.

The cross-border campaign has attracted less attention than Turkey's incursions into neighbouring Syria - partly because Turkish troops have long been in Iraq - but it is part of a strategy to push the fight beyond its borders after years of bloodshed at home.

Turkey has been battling an insurgency in its mainly Kurdish southeast by Kurdistan Workers Party militants that has killed 40,000 people since the 1980s and which has largely been directed from within Iraq.

After the breakdown of peace efforts in 2015, heavy fighting erupted again in Turkey. Since then President Tayyip Erdogan's government has sought to address what it says is the root of the crisis.

The new approach aims to destroy the threat from where it begins. It aims to deny PKK fighters any sanctuary near the border, cut their supply lines between Iraq and Syria, and prepare the ground for a possible offensive on the main PKK stronghold around the Qandil mountains, inside Iraq on the Iranian border.

Much of the new military muscle comes from domestically produced armed drones. In Iraq, that means Turkey can attack militants in areas once beyond its reach.

The use of drone technology appears to have significantly shifted the balance of power on the ground, allowing Turkish forces to go after militants in areas previously difficult to penetrate.

Baghdad summoned Turkey's ambassador last month to formally complain, but the central government has limited authority in the autonomous region, while the Kurdistan Regional Government in northern Iraq is wary of antagonising Turkey, which has NATO's second largest standing army.