At least 24 Turkish soldiers have been killed in clashes with Kurdish rebels at several police and army posts in south-east Turkey, reports say.
Governor Muammer Turker confirmed the attacks in the mainly Kurdish province of Hakkari, the Associated Press said.
The attacks come a day after a blast in the southeast Bitlis province killed five police officers and three others.
The area, where ethnic Kurds make up a majority, has recently seen a spike in violence by Kurdish rebels.
Turkey has responded with a police crackdown on suspected rebel sympathisers and air strikes on Kurdish sites in northern Iraq.
Rebels are seeking greater autonomy in the country's Kurdish-dominated south-east, and have killed dozens of members of the country's security forces, and at least 17 civilians, since mid-July.
Tens of thousands of people have died in the conflict since 1984.
'Pressure on government'
The latest violence - thought to be simultaneous overnight attacks - is said to have also taken place in several locations in Cukurca and the district of Yuksekova.
Correspondents say such attacks will add to pressure on the government to devise a more effective strategy for combating the PKK.
The government has already said it will ask the police to play a bigger role in counter-insurgency, but this idea has been challenged by critics who argue that the police are no better equipped to tackle the PKK than the army is.
The BBC's Jonathan Head, in Istanbul, says there is little talk now of renewing the so-called "democratic opening", an initiative from two years ago, which aimed to end the conflict in the south-east by expanding the rights of the Kurdish minority.
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