Russia's ambassador to Turkey has been shot and killed in a gun attack at a photo exhibition in the Turkish capital Ankara.

In a live televised statement, Maria Zakharova, a spokeswoman for Russia's Foreign Ministry said Mr Karlov - who was taken to hospital following the shooting - had died of his wounds, and also branded the attack a "terrorist act".

"Today in Ankara as a result of an attack, the ambassador of the Russian Federation to Turkey, Andrey Gennadyevich Karlov, received a wound from which he died," Ms Zakharova said, adding: "We regard this as a terrorist act."

Footage from the scene shows Mr Karlov making a speech when he is shot and falls to the floor.

The suspected gunman, who is seen wearing a suit, then raises his gun and shouts: "God is great. Don't forget Aleppo and Syria. Those who caused this cruelty in Syria will pay for this. You will take me only when I am dead."

Screaming can also be heard in the background.

Witnesses reported at least eight shots were fired.

Turkish security sources said the suspected gunman was a police officer who worked in Ankara, but was not on duty when the attack took place.

Turkish media reported that the gunman had been "neutralised".

A photo from the scene appeared to show four people, including the ambassador, lying on the ground in the gallery.

A witness to the shooting who did not wish to be identified said: "He [the suspected gunman] took out his gun and shot the ambassador from behind. We saw him lying on the floor and then we ran out."

Another witness said that while gunfire continued after Mr Karlov was shot, it had now stopped.

Russian media reported that security had been increased around the embassy in Ankara following the attack.

The mayor of the city added that the attack was an attempt to ruin relations between Turkey and Russia.

Melih Gokcek made the comments outside the hospital where Mr Karlov was taken.

A senior Russian Parliamentarian said talks between Russia, Turkey and Iran on the future of Syria will still take place in Moscow on Tuesday despite the killing.

The United Nations condemned the attack and called for the perpetrator to be brought to justice.

Russia is a close ally of Syrian President Bashar al-Assad and its air strikes were instrumental in helping Syrian forces end rebel resistance in helping Syrian forces end rebel resistance in Aleppo.

Relations between Moscow and Ankara have been fraught over the situation in Syria, with the two supporting opposing sides.

Prime Minister Theresa May reported the shooting to MPs while speaking in the House of Commons, saying the then-breaking news was a "matter of concern".

Foreign Secretary Boris Johnson could be seen leaving the chamber immediately after the Prime Minister's announcement.