Top security was enforced around the Russian embassy for their arrival, and the city of Ankara is on high alert following the killing. Several embassies have closed for the day.

There has been much speculation as to the motives of police officer of two and a half years Mevlut Mert Altintas, who fired eight bullets into the ambassador before being shot dead by police. As a relatively new recruit he would have been subject to the heavy AKP vetting all security personnel have been subject to in recent years.

BREAKING: The assailant is identified as Mevlüt Mert Altıntaş who is a police officer from Ankara. pic.twitter.com/UeIrgCMs57

— Turkey Untold (@TurkeyUntold) 19 dicembre 2016

Lax security at the art gallery venue may also be a factor.

Turkish police have now arrested seven people, mainly members of Altintas’s family including his parents and sister, in connection with the murder.

#Lavrov and @JZarif laid flowers in memory of Russian Ambassador to #Turkey Andrey #Karlov killed yesterday in #Ankara pic.twitter.com/NKaF9oGl6B

— MFA Russia ?? (@mfa_russia) 20 dicembre 2016

One senior official said there were “strong signs” the attacker had been a member of the network allegedly run by US Turkish exile Fethullah Gulen, accused of planning the abortive July coup. (Euronews)