The attacks come amid a surge in violence by Kurdish rebels, prompting Turkey's army chief to highlight the danger posed by a militant safe haven in northern Iraq from where they launch their attacks into Turkey.

Most of the casualties were from a clash that broke out when Kurdistan Workers' Party (PKK) rebels fired upon a military outpost overnight Monday in a rural area in Hakkari province near the borders with Iraq and Iran, the army said in a statement on its website.

Three soldiers and 11 PKK rebels were killed in the fighting in which the army used unmanned drones to detect the fleeing militants, it added. Three other soldiers were wounded.

In a separate incident, six soldiers were lightly wounded late Monday when PKK rebels opened fire on troops on security duty at an outpost in the eastern province of Elazig, the army said.

A PKK rebel was killed when soldiers returned fire, it added.

In other incidents in Hakkari late Monday, two soldiers were wounded when they were fired upon and another two stepped on a landmine planted by the rebels, Anatolia news agency reported.

The PKK, listed as a terrorist group by Turkey and much of the international community, has dramatically stepped up violence since its jailed leader Abdullah Ocalan said through his lawyers in May he was abandoning efforts to seek dialogue with Ankara.

In remarks late Monday, chief of general staff Ilker Basbug described the safe haven the militants enjoy in northern Iraq, an autonomous region run by the Iraqi Kurds, as "the greatest threat" facing Turkey, Anatolia reported.

The PKK could pose security threats also for Iraq after US troops withdraw from the country, Anatolia quoted him as saying in a television programme.

"The PKK presence in the north of Iraq could have a negative impact on Turkish-Iraqi ties. In a sense, it could have a negative impact also on Turkish-US ties," he said.

The PKK has long taken refuge in remote mountains in the region, using bases there as a launching pad for attacks across the border.

Ankara had often accused the Iraqi Kurds of tolerating and even aiding the PKK, but has recently shifted to a policy of seeking cooperation with them to curb the group.

The United States has pledged support against the PKK, supplying its NATO ally with intelligence on rebel movements in northern Iraq to back up Turkish air raids against PKK hideouts in the region.

The surging violence has dealt a severe blow to an already fragile government initiative to boost Kurdish freedoms and investment in the impoverished southeast in a bid to erode separatist sentiment among the Kurds and cajole the PKK into laying down arms.

Ankara however rejects dialogue with the PKK, insisting the rebels should either surrender or face the army. The PKK took up arms in 1984, sparking a conflict that has claimed some 45,000 lives.