A Turkish military helicopter crashed Saturday in the southeastern city of Siirt, killing all 17 troops on board.

A Turkish military helicopter crashed Saturday in the southeastern city of Siirt, killing all 17 troops on board, local officials said.

An investigation was ongoing to determine why the Sikorsky chopper went down, Siirt province governor Ahmet Aydin said.

The helicopter might have hit a hill or a rock outcropping due to stormy weather in the area, according to Turkish media.

The helicopter was transporting troops to Siirt's Pervari district, where the Turkish army has been engaged in a land operation against Kurdish rebels for three days, security sources told Agence France Presse.

 Last month a Sikorsky crashed in southeastern Diyarbakir province after it hit power lines, killing one soldier and wounding seven.