The gunman was killed by special forces.
The Russian ambassador to Turkey Andrei Karlov was shot in the back and killed as he gave a speech at an Ankara art gallery on Monday by an off-duty police officer who shouted "Don't forget Aleppo" and "Allahu Akbar" as he opened fire.
At a special meeting at the Kremlin, President Vladamir Putin ordered increased security at all Russian missions and said "the bandits" who committed the act would feel retribution.
The gunman was identified as 22-year-old, Mevlut Mert Altintas, who had worked for the Ankara riot police for two and a half years.
"We regard this as a terrorist act," said Russian Foreign Ministry spokeswoman Maria Zakharova. "Terrorism will not win and we will fight against it decisively. Gunman belonged to the network of the US-based cleric Fethullah Gulen".
The government says Gulen, who has lived in self-imposed exile in the US state of Pennsylvania since 1999, created a "parallel network" in the police, military, judiciary and civil service aimed at overthrowing the state.
1. Russian envoy Andrei Karlov giving his speech
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Russian Ambassador, Andrei Karlov makes a speech at an art gallery shortly before he was shot in Ankara, Turkey, December 19, 2016. (Image credit: Reuters)
2. Karlov shot down as gunman shouts 'Don't forget Aleppo'
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Andrei Karlov lies on the ground after he was shot by Mevlut Mert Altintas, a Turkish off-duty police officer. Altintas shouted "Don't forget Aleppo" and "Allahu Akbar" as he opened fire in the art gallery. (Image credit: Reuters)
3. Panicked visitors
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People crouch in a corner of the art gallery to save their lives.Three of the visitors were injured in the firing. (Image credit: PTI)
4. Turkish police secures the area
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Turkish police officers cordon off the area close to the art gallery after the shooting. (Image credit: PTI)
5. Paying homage
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A man lays a flower at the Russian Foreign Ministry in Moscow following the assassination. (Image credit: AFP)
