Seventeen Turkish soldiers were killed when their helicopter crashed in southeastern Turkey due to bad weather conditions.
Area governor Siirt Governor Ahmet Aydin said the Sikorsky helicopter crashed on Herekol mountain, in the Pervari area of Siirt province on Saturday.
He said the victims were members of gendarmerie special forces and there were no survivors.
The Turkish military has been carrying out operations on the mountain in recent months to flush out militants from outlawed separatist group the Kurdistan Workers Party (PKK) who have hideouts there, Reuters reports.
Turkish jets and helicopters have pounded PKK positions along the border with Iraq and Iran for three days, killing 42 militants, the governor said.
More than 40,000 people have been killed in the conflict between Turkey and the PKK, which launched its insurgency in 1984 with the aim of carving out a separate state in mainly Kurdish southeast Turkey.