Turkish warplanes hit Kurdish militant targets, including training camps, shelters and ammunition storage areas in Iraq and northern Syria, the Turkish Defence Ministry said on Wednesday.

The air strikes are part of an ongoing Turkish campaign in Iraq and Syria against militants of the Kurdistan Workers Party (PKK) and the Syrian Kuridsh YPG militia, both of which Turkey regards as terrorist groups.

Turkish Defence Minister Hulusi Akar said on Wednesday that the operation had been successful and that "many terrorists" were killed.

"Only terrorists and targets belonging to terrorists were hit. The terrorists' shelters, bunkers, inns, caves were brought down on their heads. The terrorists have once again felt the breath of the Turkish Armed Forces on their necks," Akar said.

Iraq's military condemned what it called a Turkish infiltration into Iraqi air space as a violation of its sovereignty. Baghdad is widely viewed, however, to be giving Ankara free rein to attack the militants.

All the planes taking part in the operation, which it said targeted the areas of Derik, Sincar and Karacak, subsequently returned to their bases. It did not provide any information on casualties resulting from the strikes.

"Terrorists' shelters, caves, tunnels, ammunition depots and so-called headquarters and training camps were targeted," the ministry statement said, without specifying exactly when the strikes occurred.

It said the air operation targeted PKK militants, which have bases in Iraq, as well as the Syrian Kurdish YPG militia.

Iraqi security officials, who spoke on condition of anonymity, said at least 20 air strikes had hit inside Iraq in the Sinjar (Sincar) mountain area.

Sinjar mountain, home to Iraq's Yazidi minority, is an area controlled variously by different armed forces and armed groups where PKK militants and their local allies operate.

The Kurdistan region of Iraq's counter-terrorism service said several people had been killed and injured in the air strikes in Iraq and Syria but provided no further details.

The PKK took up arms against the Turkish state in 1984. More than 40,000 people have been killed in the conflict, which in the past was mainly focused in southeast Turkey.

Turkish officials privately say they believe Baghdad is firmly on their side in fighting the PKK.

Reuters