Vladimir Putin pays respects to murdered ambassador Andrey Karlov

Russia's ambassador to Turkey, who was murdered by a man shouting "Allahu Akbar" and "Don't forget Aleppo", has been laid to rest at a ceremony in Moscow attended by President Vladimir Putin.

Diplomats and family members gathered at the Foreign Ministry building in the centre of the capital to pay their respects to Andrey Karlov, who was shot dead at an art exhibition in Ankara on Monday.

Television footage showed the 62-year-old's body lying in an open casket in the marble-clad lobby of the building, flanked by uniformed honour guards.

Mourners, who also included Prime Minister Dmitry Medvedev and Foreign Minister Sergei Lavrov, approached to lay flowers.

Turkey has identified the assassin as Mevlut Mert Altintas, 22, who had worked for Ankara's riot police. He was killed in a shootout with police.

Mr Karlov's body was repatriated to Moscow on Tuesday.

During a ceremony at Moscow's Vnukovo Airport the diplomat's widow wept as his coffin was carried from the runway to a hearse.

Earlier, the same plane carried 18 Russian investigators and officials to Ankara to participate in an investigation into the killing.

The Kremlin has refused to speculate whether Altinas was operating as a lone wolf or as part of a bigger operation, but said the murder was a blow to Turkey's prestige.

Turkish President Recep Tayyip Erdogan has claimed Altintas was a follower of Fethullah Gulen, a US-based Muslim cleric who was blamed for orchestrating a failed coup in July.

Mr Erdogan said Altinas was part of what he calls the "Fethullah Terror Organisation".

He added that Turkey's intelligence agency was also looking into Altintas' possible foreign connections, saying there were "certain clues" indicating overseas links.

US State Department spokesman John Kirby dismissed "absolutely false" claims there was American involvement or support in the assassination.

He said: "We need to let the investigators do their job and we need to let the facts and the evidence take them where it is before we jump to conclusions."

Russia and Turkey have said the murder will not harm relations between the two countries, which have been strained over Syria.

Turkey's state-run news agency said authorities have released six members of Altintas' family who were detained for questioning in the aftermath of the killing.

A total of 11 people were detained, including his parents, sister and three other relatives. Those still in custody include Altintas' roommate.