Russia's ambassador to Ankara Andrey Karlov was on Monday badly wounded in a gun attack while visiting an art exhibition opening in the Turkish capital, television reports said.
Karlov was hospitalised and several other people were wounded in the attack by an unknown gunman, NTV and CNN-Turk televisions said.
The attack came after days of protests in Turkey over Russia's role in Syria, although Moscow and Ankara are now working closely together to evacuate citizens from Aleppo.
Pictures published by the Hurriyet daily showed at least two men in suits lying flat on the ground as another man brandished a gun.
The attack happened at the Cagdas Sanatlar Merkezi, a major art exhibition hall in the Cankaya district of Ankara where most foreign embassies are located including Russia's mission.
CNN-Turk said the ambassador was in a serious condition.
Protesters in Turkey have held Moscow responsible for human rights violations in Aleppo.