Two Turkish soldiers were killed in southeast Turkey on Tuesday in a roadside bomb attack on their vehicle blamed on Kurdistan Workers' Party (PKK) militants, security sources said.

The soldiers were killed by the bomb planted in the Silvan district of the mainly Kurdish Diyarbakir province, the sources told AFP. Four other soldiers were wounded in the attack.

The Turkish government has been waging a relentless offensive aimed at crippling the PKK, which has staged a string of attacks against security forces in Turkey since a two-year-old ceasefire fell apart in late July.

The violence has destroyed hopes of fresh talks to end a conflict that has claimed tens of thousands of lives since 1984.

The latest attack comes after two protesters were killed in clashes with police in Diyarbakir city on Monday, amid growing anger over the imposition of curfews to back up anti-PKK operations.