Twelve Turkish police have been killed in a new attack blamed on Kurdish militants as violence in the southeast threatened to spiral out of control.
It followed Ankara's launch of a massive wave of air strikes against rebel strongholds in northern Iraq.
The 12 police were killed in the eastern region of Igdir in a bomb attack by Kurdistan Workers' Party (PKK) militants on a minibus taking them to the Dilucu border post with neighbouring Azerbaijan, the state-run Anatolia news agency reported.
The attack came two days after 16 Turkish soldiers were killed in a twin roadside bomb attack in Daglica in the southeastern region of Hakkari, according to the army, the deadliest strike in the current phase of the conflict.
Their deaths prompted Prime Minister Ahmet Davutoglu to vow to "wipe out" PKK militants from the mountains of eastern Turkey.
The PKK, known for sometimes exaggerating the death tolls of its attacks, said 31 Turkish soldiers had been killed in Sunday's (local time) gun and bomb attack in Daglica.
Turkey has staged air strikes and ground operations against the PKK in its strongholds of southeastern Turkey and northern Iraq in a bid to inflict a mortal blow on its capacities.
But the PKK has hit back, killing dozens of Turkish police and soldiers in almost daily attacks, with the bloodier attacks marking a new intensification of the conflict.
In response to the Daglica attack, Turkish warplanes launched a massive air operation early Tuesday in northern Iraq, killing as many as 40 rebels, Anatolia said.
More than 50 Turkish jets were involved in the six hours of raids, killing "35 to 40 terrorists according to preliminary findings", it added.
"These terrorists must be wiped out from the mountains," Prime Minister Ahmet Davutoglu said Monday.
The violence has left in tatters a 2013 ceasefire aimed at allowing a final peace deal to end the PKK's three-decade insurgency, which has claimed tens of thousands of lives.
The PKK initially took up arms in 1984 with the aim of establishing an independent state for Turkey's Kurdish minority, although lately the demands focused on greater autonomy and rights.
Commentators have expressed alarm that the current situation increasingly resembles the worst days of the PKK's insurgency in the 1990s when attacks on this scale were commonplace.