Photographer Burhan Ozbilici was attending a routine job at the opening of a photography exhibition in Ankara, Turkey.

But the event descended into horror when the Russian ambassador to Turkey, Andrei Karlov, was assassinated by a local police officer later identified as Mevlut Mert Altıntas.

The Associated Press photographer captured the murder in astonishing detail and reflected on the incident in a piece for Associated Press.

"It was a coolly calculated assassination, unfolding in front of me and others who scrambled, terrified, for cover as the trim man with short hair gunned down the Russian ambassador," he said. "I was afraid and confused, but found partial cover behind a wall and did my job: Taking photographs."

This is the story of how Karlov's death unfolded, through the eyes of Ozbilici.

"I decided to attend simply because it was on my way home from the Ankara office," Ozbilici told AP. "After Russian Ambassador Andrei Karlov began to make his address, I moved closer to photograph him, thinking the pictures would come in useful for stories on Turkish-Russian relations."

The gunman, a Turkish policeman, can be seen standing behind the Russian ambassador to Turkey, Andrei Karlov, before he opened fire (AP)

"He was speaking softly and — from what I could tell — lovingly about his homeland," Ozbilici added. "Then came the gunshots in quick succession, and panic in the audience. The ambassador's body lay on the floor, just meters away from me."

Picture: (AP/Burhan Ozbilici)

Ozbilici said there was panic in the audience. He captured a child being pulled to safety.

Ozbilici said: "I couldn't see any blood around him; I think he may have been shot in the back. It took me a few seconds to realise what had happened: A man had died in front of me."

The gunman stands over the body of Russian Ambassador to Turkey, Andrei Karlov, at a photo gallery in Ankara, Turkey (AP)

Ozbilici moved to the left of the gallery, while others were "cowering on the right side" of the room. He recalled the gunman shouting "Allahu Akbar."

People in the art gallery react moments after the Russian ambassador to Turkey, Andrei Karlov, was shot dead (AP)

"He walked around the ambassador's body, smashing some of the photos hanging on the wall," Ozbilici said. The photographer advanced a little thinking: "Even if I get hit and injured, or killed, I'm a journalist. I have to do my work."

A man gestures near to the body of a man at a photo gallery in Ankara, Turkey (AP)

"As my mind raced, I saw that the man was agitated — and yet he was strangely in control of himself. He shouted at everyone to stand back. Security guards ordered us to vacate the hall and we left."

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