At least four soldiers were martyred when a military helicopter crashed Monday during an emergency landing in Istanbul, the provincial governor said.
Ali Yerlikaya told reporters the helicopter crashed near a residential area in Cekmekoy district at 6.51 p.m. local time (1551GMT).
The cause of the crash remains unknown, he added.
The National Defense Ministry confirmed the death toll in a tweet and said an investigation into the crash was launched.
"Following a comprehensive investigation, the result will be shared," it said.
Parliament Speaker Binali Yildirim expressed sadness and extended condolences on Twitter.
Main opposition Republican People's Party (CHP) leader Kemal Kilicdaroglu also offered his condolences.
Turkish court imposed a broadcast ban to prevent misinformation.