A Turkish military helicopter crashed three minutes after takeoff on Wednesday evening, killing all 13 personnel, the Turkish military said.

The Cougar-type helicopter hit a high-voltage power line after taking off from a base east of Sirnak, near the border with Iraq, a statement from the General Staff said. 

Several of those killed were officers, including a major general in charge of military operations against militants from the Kurdistan Workers' Party (PKK) in the region.

The military's statement was contradicted a day later, when PKK said militants fired on the helicopter and forced it to take evasive action. 

"A cougar-type helicopter carrying the coordination forces of the operation of the occupying Turkish army... was taken under fire by one of our unit," the PKK said. "The helicopter which was hit has crashed while trying to get away from the area."

The crash comes as the Turkish military battles the PKK in the mountainous and porous border region.

Read: The Middle East's complex Kurdish landscape

The unverified PKK claim, if confirmed, is likely to raise further concern in Turkey over the US supplying weapons to Syrian Kurdish forces fighting the "Islamic State" in Syria. Turkey claims the Syrian Kurdish fighters, or YPG, are the same as the PKK. 

At least 2,844 people have been killed, including 944 security force members and 1,286 Kurdish militants, since a two-and-half year ceasefire broke down in July 2015, according to the International Crisis Group.