The secret services of a Nato country is "highly likely" to have been behind the assassination of ambassador Andrei Karlov, claimed a top ally of Vladimir Putin.
Senior senator Frantz Klintsevich, deputy chairman of the Russian upper chamber's defence and security committee, said: "It was a planned action.
"Everyone knew that he was going to attend this photo exhibition.
"It can be Isis, or the Kurdish army which tries to hurt Erdogan.
"But may be - and it is highly likely - that representatives of foreign NATO secrets services are behind it.