Fighting erupted Monday between soldiers on patrol and Kurdistan Workers' Party (PKK) rebels in the mountainous Bestler region of Sirnak province, on the border with Iraq and Syria, the local governor's office said in a statement.

PKK rebels who use bases in neighbouring northern Iraq to stage attacks on Turkish territory are known to be active in Bestler.

The PKK, listed as a terrorist organisation by Ankara and much of the international community, notably stepped up violence this year.

The army has launched a large-scale operation against the group in eastern and southeastern Turkey and massed troops on the border with Iraq, fuelling talk of a cross-border operation to strike at rebels camps there.

According to a tally compiled by human rights activists from official and independent sources, 111 members of the security forces, 109 PKK rebels and five civilians were killed in the first six months of the year in eascalating violence in the region.

The PKK took up arms for self-rule in Turkey's mainly Kurdish east and southeast in 1984. The conflict has claimed more than 37,000 lives.