"All targets were hit successfully," the general staff said in a statement about Tuesday's bombing raid on Kurdistan Workers' Party (PKK) positions in northern Iraq.

The targets in three regions along the Turkish border included two anti-aircraft posts, four ammunition depots as well as training and logistical bases.

"Work is underway to determine the losses of the terrorists," it said.

Tuesday's raid was the fourth strike on PKK targets in northern Iraq that the Turkish army has confirmed since December 16, in addition to a ground cross-border operation to stop a group of rebels trying to infiltrate Turkey.

At least 150 PKK militants have been killed in the air raids so far and more than 200 rebel positions destroyed, according to the army.

Iraqi Kurds, who run northern Iraq, reported two other air strikes in December that Ankara did not confirm.

The raids are conducted with intelligence from the United States, which, like its NATO ally Turkey, lists the PKK as a terrorist group.

Earlier Friday, the military said 10 PKK rebels had turned themselves in to the authorities in southeast Turkey, bringing to 21 the number of militants to surrender in the past month.

The militants "fled the terrorist organisation's camps in northern Iraq and surrendered to the security forces in Silopi on January 17," the statement said.

The surrenders are a sign of "disintegration" within the PKK amid an intensified clamp down on the group, it said.

Ankara says an estimated 4,000 PKK militants take refuge in northern Iraq, where they are tolerated by the local Kurdish administration as they use camps there as a springboard for attacks inside Turkey.

Faced with mounting PKK violence, the Turkish government secured in October a one-year parliamentary authorisation for cross-border military action against the rebels.

The PKK, listed as a terrorist group by Ankara and much of the international community, has waged a bloody campaign for Kurdish self-rule in southeast Turkey since 1984. The conflict has claimed more than 37,000 lives.