Two Turkish soldiers were killed and dozens wounded Sunday in a suicide attack claimed by Kurdish militants, as Ankara kept up its air campaign against the rebels' bases in northern Iraq.
The attack in the Dogubayazit district of the eastern Agri province is the first time Kurdistan Workers' Party (PKK) militants have been accused of staging a suicide attack in the current crisis, amid an escalating cycle of violence.
Ankara has launched a two-pronged "anti-terror" offensive against Islamic State jihadists in Syria and PKK militants based in northern Iraq after a series of attacks inside Turkey including a devastating suicide bombing blamed on the IS group.
But so far the bombardments have focused far more on the Kurdish rebels -- with Turkish official media claiming that 260 suspected PKK members have been killed -- and the militants have retaliated inside Turkey.
There is also growing controversy over possible civilian casualties in the Turkish bombings, and the local Kurdish authorities in northern Iraq on Saturday urged the PKK to spare civilians.
The suspected PKK suicide bomber drove a tractor laden with two tons of explosives up to the military station in the Dogubayazit district, the official Anatolia news agency reported, quoting the local governor's office.
Two soldiers were killed and 31 were wounded, four seriously, the army said. In a statement, the PKK claimed the attack as a "sabotage event".
The soldiers were deployed with the local Jandarma (Gendarmerie), a branch of the army that looks after internal security in Turkey.
Such was the power of the blast that houses in a village several hundred metres (yards) away were hit by debris and several villagers slightly injured, the Dogan news agency said.
PKK militants who took part in the operation also launched ambushes on the roads to prevent medical teams reaching the scene before fleeing in the direction of Mount Ararat, it added.
In a separate incident also blamed on the PKK, one Turkish soldier was killed and seven were wounded when a mine exploded as their convoy was travelling on a road in the Midyat district of Mardin province in southeastern Turkey, the army said.
The PKK insurgency for greater rights and powers for Turkey's Kurdish minority has claimed tens of thousands of lives since it began more than 30 years ago. The current fighting has left a 2013 ceasefire in tatters.
According to an AFP toll, at least 17 members of the security forces have now been killed in attacks blamed on the PKK since the fresh crisis erupted last week.
The violence is the most severe in Turkey since the 2013 ceasefire, which raised hopes of finding a peace deal and sealing a historic reconciliation between the modern Turkish state with Kurds, by far its largest minority.
Turkey's Kurdish militants have sought cover in neighbouring northern Iraq where the presence of the PKK has long been tolerated in Iraq's Kurdish-ruled region. More fighters also crossed into the area from Turkey as part of the 2013 ceasefire.
But the office of the region's president Massud Barzani said in a statement Saturday that the PKK rebels must "keep the battlefield away from the Kurdistan region" to prevent civilian casualties.
Turkey's pro-Kurdish People's Democratic Party (HDP) said 10 civilians, including a pregnant woman, were killed early Saturday in a Turkish air strike on a Kurdish village in northern Iraq.
The Turkish foreign ministry promised a "full investigation" into the claims. But the army denied the charges, saying "no civilian locations were to be found in the vicinity affected by the bombing".
The government has vowed to press on with the over week-long bombing campaign against the PKK, saying Saturday that "for the peace and security of our people, the fight against terror organisations will continue without interruption".
The impact of the bombing campaign -- which has seen daily raids by dozens of Turkish F-16s on PKK holdouts in remote mountain territory in northern Iraq -- remains unclear.
Anatolia reported the group's leadership has split into three to protect itself from further air strikes.
One group will stay at its headquarters on Qandil Mountain in northern Iraq, one has gone to a Kurdish-controlled region in Syria and another, including top PKK leader Murat Karayilan, has fled to Iran, it said.