Interior Minister Suleyman Soylu told reporters at the scene, Censor.NET reports citing Interfax.
The officer, Mevlut Mert Altintas, 22, shot and killed 62-year-old Ambassador Andrey Karlov while he was giving a speech Monday night at an art gallery opening, Suleyman Soylu said.
He said two more people were injured in the attack and promised to investigate the attacker's contacts.
Journalist Osman Pashayev said Altintas struck no one as suspicious as he used his police identification badge to enter the gallery with a gun when he was not on duty.
Osman Pashayev also published translation of Altintas' remarks: "Don't forget Halep (Aleppo)! Don't forget Syria! Don't forget Halep! Don't forget Syria! You will not taste safety unless our cities are safe. Only death can take me out of here. Whoever has a share in this tyranny will pay for it one by one."
As reported, the Russian diplomat was shot dead by a gunman in Turkish Ankara's Contemporary Arts Gallery at the opening of exhibition called "Russia through Turks' eyes" Dec. 19.
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