New footage shows the Istanbul nightclub gunman spraying a hail of bullets into the street and shooting people at the entrance to Reina.
In the video, bullets fired by the unknown attacker's assault rifle hit passing cars and send sparks flying into the air — before he is shown shooting dead a person at point-blank range as others dive for cover.
Separate surveillance footage from across the street was released by Turkey's Dogan news agency and depicts the opposite angle from the brutal recording that shows the gunman, who officials now believe to have been an operative of Isis, rushing into the nightclub.
Hurriyet and Karar newspaper reports cited unnamed security officials saying that authorities have determined that the gunman comes from a Central Asian nation and is believed to be either from Uzbekistan or Kyrgyzstan.
Police had also established similarities with the high-casualty attack at Ataturk Airport in June and was investigating whether the same Isis cell carried out both attacks. Isis claimed responsibility for the attack.
The gunman, who is still at large, killed a policeman and another man outside the Reina club in the early hours of 2017 before firing at people partying inside. Turkish media reported he had fired up to 180 shots.
Nearly two-thirds of the dead were foreigners, many from the Middle East.
Mehmet Dag, who watched the catastrophe unfold from the street, said: “The man targeted the security there ... he took most of them down and went inside.
“Once he went in, we don't know what happened. There were gun sounds and after two minutes, the sound of an explosion.”
Hundreds of revellers had come to see in 2017 at the club on the shores of the Bosphorus river, renowned for being a chic party spot for celebrities from Turkey and the rest of the world.
Turkish footballer Sefa Boydas, of Beylerbeyi, said: “Just as we were settling down, by the door there was a lot of dust and smoke. Gunshots rang out.
“When those sounds were heard, many girls fainted.”
Mr Boydas recounted how panic quickly ensued as hundreds of people fled, with many being crushed amid the desperate attempts to stay alive. The screams drowned out anything the gunman was saying, he said.
President Recep Tayyip Erdogan accused groups like Isis of trying “to create chaos”.
“They are trying to... demoralise our people and destabilise our country,” he added.
