Watch: Unseen horrific clip of Russian ambassador's assassination emerges

Dubai - The assassin casually paces behind the ambassador, positions himself, and waits for the right moment.

Barely hours after pictures of a suited assassin brandishing a gun spread like wildfire across the world, fresh footage of the killing has emerged.

The video, a little over a minute long, shows the off-duty policeman standing behind Russian ambassador to Turkey Andrey Karlov, casually pacing the floor behind him.

After the first few seconds into the video he finally positions himself diagonally behind the ambassador, to his right, and waits for the right moment, before whipping out his gun and pumping bullets into the ambassador.

Earlier today, Turkish police detained six people over the assassination, state media said, widening a probe to relatives of the off-duty policeman who shouted "Don't forget Aleppo!" as he gunned the envoy down.

Both countries cast Monday's attack, which occurred at an art gallery in the capital Ankara, as an attempt to undermine a recent thawing of ties that have been strained by Syria's civil war, where they back opposing sides.