A gunman crying “Aleppo” and “revenge” shot and killed Russia's ambassador to Turkey while he was visiting an art exhibition in Ankara on Monday, witnesses and media reports said.
Foreign Ministry spokeswoman Maria Zakharova made the announcement in a live televised statement.
Three other people were wounded in the attack, NTV and CNN-Turk television stations said.
Television footage showed a man in a dark suit and tie waving a gun and gesturing in the air.
The state-run Anadolu news agency said the gunman had been “neutralised” in a police operation, without giving further details.
The Kremlin said President Vladimir Putin had been informed.
The incident 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 the battered city of 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.
'People fleeing'
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.
“It happened during the opening of an exhibition,” Hurriyet correspondent Hasim Kilic, who was at the exhibition, 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.
The Russian foreign ministry spokesman added that medics were trying to treat the envoy at the scene but that shooting continued, retracting an earlier report that he was taken to hospital.
Protesters in Turkey have held Moscow responsible for human rights violations in Aleppo.
The attacker remained inside the building after and television as clashes were continued.
Turkish Interior Minister Suleyman Soylu was at the scene to supervise a police operation, Turkish television said.
The attacker was “neutralised” in the operation, Anadolou said.
US condemns attack on Russian ambassador to Turkey
The United States condemns the gun attack on the Russian ambassador to Turkey earlier on Monday, the US State Department said.
Ambassador Andrei Karlov died of his gunshot wounds after he was attacked at an art gallery in the Turkish capital Ankara on Monday, the Russian RIA news agency reported.
“We condemn this act of violence, whatever its source,” said US State Department spokesman John Kirby in a statement.
“Our thoughts and prayers are with him and his family.”
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.
