Three soldiers of the Turkish security forces and nine of the outlawed Kurdish Workers' Party ( PKK) were killed in an armed clash in southeastern Turkey, the semi-official Anatolia news agency reported Tuesday.

A group of PKK rebels armed with long-range weapons attacked a Turkish military outpost in Semdinli town of Hakkari province early on Tuesday, killing three soldiers and wounding another three, the report said.

Nine PKK members were also killed in the clash, the report said, adding large-scale operation was launched in pursuit of the region's PKK rebels.

Meanwhile, another PKK group fired at a military patrol in the Yuksekova town of Hakkari province, injuring two soldiers.

The Turkish armed forces said the PKK might intensify attacks over the summer when more PKK guerrillas arrive in Turkey from the mountainous areas in northern Iraq during warmer weather.

The PKK, labeled as a terrorist group by the Turkish government, the United States and the European Union, took up arms in 1984 to create an ethnic homeland in southeastern Turkey. Some 40,000 people have been killed in the conflicts since then.