The security forces used helicopters to mount an attack on a group of eight separatist militants from the Kurdistan Workers' Party (PKK) in Sirnak in southeast Turkey, two kilometres (just over a mile) from where five Turkish soldiers were killed on Tuesday. Two of the soldiers died in a mine explosion and a further three were killed by rebels.

Two of the rebels escaped under cover of darkness and the army is now combing the majority Kurdish mountainous region of south-east Anatolia, the sources added.

The burials last week of rebels killed by Turkish security forces sparked several days of riots in the region.

Twelve people were killed in the worst urban unrest in the country for years and a further three died when PKK sympathisers threw molotov cocktails in Istanbul, in the northeast of the country.

The PKK, branded a terrorist organisation in Turkey and the West, has been waging an armed campaign for Kurdish self-rule in the southeast since 1984. The conflict has claimed some 37,000 lives.