The shooting took place 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.
"It happened during the opening of an exhibition," Hurriyet correspondent Hasim Kilic, who was at the scene, told AFP.
"When the ambassador was delivering a speech, a tall man wearing a suit, fired into the air first and then took aim at the ambassador," said Kilic. "He said something about Aleppo and 'revenge'. He ordered the civilians to leave the room. When people were fleeing, he fired again," he added.
Protesters in Turkey have held Moscow responsible for human rights violations in Aleppo. Turkish Interior Minister Suleyman Soylu was at the scene to supervise a police operation, Turkish television said.
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Turkey and Russia saw relations plunge to their worst levels since the Cold War last year when a Turkish jet shot down a Russian war plane over Syria. They stand on opposite sides of the Syria conflict with Ankara backing rebels trying to topple Moscow ally President Bashar al-Assad.
But the rhetoric has warmed considerably since a a reconciliation deal was signed earlier this year and a Russian and Turkish-brokered deal has helped the evacuation of citizens from Aleppo in the last days.
The attack comes a day before Turkish Foreign Minister Mevlut Cavusoglu, Russian counterpart Sergei Lavrov, and Foreign Minister Mohammad Javad Zarif of Iran, Assad's other key ally, were to hold unprecedented tripartite talks on the Syria conflict in Moscow.
A Turkish official on Monday denied Ankara had forged any secret "bargain" with Moscow over the future of Syria, despite the improving cooperation that led to the deal for evacuations from Aleppo.
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