By Stuart Williams
A car bomb attack has killed two Turkish soldiers in the Kurdish-dominated southeast of the country, after separatist rebels warned they would no longer observe a truce after Ankara's air strikes on their positions in Iraq.
Turkey has launched a two-pronged "anti-terror" cross-border offensive against Islamic State (IS) jihadists and Kurdistan Workers Party (PKK) militants after a wave of violence in the country, pounding their positions with air strikes and artillery.
But the expansion of the campaign to include not just IS targets in Syria but PKK rebels in neighbouring northern Iraq bitterly opposed to the jihadists has put in jeopardy a truce with the Kurdish militants that has largely held since 2013.
The PKK on Saturday said the conditions were no longer in place to observe the ceasefire, following the heaviest Turkish air strikes on its positions in northern Iraq since August 2011.
The car bomb went off as the soldiers were travelling on a road in the Lice district of Diyarbakir province late Saturday.
"Two of our personnel were killed in the heinous attack, four were wounded," a statement from the local governor's office said, adding that large-scale operations have been launched to find the perpetrators. There was no immediate claim of responsibility.
The PKK has for decades waged a deadly insurgency in the southeast of Turkey for self-rule that has claimed tens of thousands of lives. A peace process that began in 2013 has so far failed to yield a final deal.
"The ceasefire appears to be over," said David Romano, Professor of Middle East Politics at Missouri State University said.
Turkish armed forces on Saturday pressed on with a new wave of strikes against IS and PKK targets, but there were no reports of new air raids overnight.
The military wing of the PKK said in a statement that one PKK fighter in northern Iraq - named as Onder Aslan - was killed in air strikes overnight Friday to Saturday and three others wounded.
The president of the Kurdish-ruled autonomous region in northern Iraq, Massud Barzani, expressed "displeasure with the dangerous level the situation has reached," his office said.
Prime Minister Ahmet Davutoglu ordered the launch of campaign after a week of violence in Turkey which began last Monday with a suicide bombing blamed on IS in a town close to the Syrian border that killed 32.
This incensed Turkey's Kurds who have long accused the government of actively colluding with IS, allegations Ankara categorically denies.
The violence has fanned fears that the conflict in Syria's civil war between IS and Kurdish militias allied to the PKK is spilling into Turkish territory.
With Turkey still without a permanent government after a June 7 election resulted in the ruling Justice and Development Party (AKP) losing its overall majority for the first time since 2002, parliament has been summoned to meet on Wednesday to discuss the security situation.