Tunceli lawmaker Huseyin Aygun was kidnapped by members of the Kurdistan Workers' Party (PKK) after his car was stopped by the rebels on the highway, security sources told AFP.

The rebels let Aygun's assistant and a journalist accompanying them leave as they took Aygun and disappeared into the woods nearby, Tunceli governor Mustafa Taskesen told reporters, citing witnesses.

The abduction was also confirmed by the CHP, the main opposition party with 135 lawmakers in the 550-seat Turkish parliament.

The incident follows the abduction of three soldiers last week in another part of Turkey's Kurdish-majority south-east.

Turkish security forces launched an operation to locate Aygun, as the search continued for the kidnapped troops.

Kurdish rebels frequently kidnap workers, soldiers and local authorities to bargain for the release of captured rebels. Those who have not been found by Turkish forces are reportedly held captive in hideouts across Turkey's border with Iraq.

Last Sunday, Kurdish rebels stormed a Turkish army post on the Iraq border, triggering fighting that killed 22 people in the latest clash since Ankara unleashed a major offensive against the insurgents.

A series of similar assaults against troops in the Kurdish-dominated south-east prompted the army to launch an all-out offensive against PKK bases in the area last month.

At least 115 rebels have been killed since the offensive began on July 23, Turkish authorities said. The abductions might be a response on the part of the rebels, according to Turkish media.

The PKK, considered a terrorist organisation by Turkey and much of the international community, took up arms in the south-east in 1984, sparking a conflict that has claimed some 45,000 lives.