It's emerged the gunman who shot at hundreds of revellers in an Istanbul nightclub left his gun then fled with distraught partygoers.
A massive manhunt is under way after the attack at Reina nightclub about 1.15am local time on Sunday (11.15 NZT) which left 39 people dead including, officials say, at least 15 foreigners.
As many as 600 people were thought to have been inside when the gunman shot dead a policeman at the door and forced his way in.
After the attack, at least 69 people were being treated in hospital, officials said, with three in a serious condition. The death toll was expected to rise.
Istanbul-based freelance journalist Hannah Lucinda Smith told RNZ the nature of the shooting has led authorities to believe it is a terrorist attack.
Ms Smith says Reina club is very popular with tourists and celebrities and 24 of the 39 dead are foreigners.
The dead included citizens from Israel, France, Tunisia, Lebanon, India, Belgium, Jordan and Saudi Arabia, officials said.
The attacker left his gun before "taking advantage of the chaos" and fleeing the scene, Turkey Prime Minister Binali Yildirim said.
He also confirmed the gunman was not dressed as Santa Claus, contradicting earlier reports.
Eyewitnesses described seeing dozens of bodies lying on the floor. Some revellers reportedly threw themselves into the Bosphorus Strait to escape the carnage and died in the icy waters.
"Gunshots rang out. When those sounds were heard, many girls fainted," professional footballer Sefa Boydas told AFP news agency.
He said people appeared to be crushed as they ran away. "They say 35 to 40 died but it's probably more because when I was walking, people were walking on top of people."
President Recep Tayyip Erdogan blamed terror groups "trying to create chaos".
"They are trying to ... demoralise our people and destabilise our country," he said.
Earlier, Interior Minister Suleyman Soylu confirmed a "manhunt for the terrorist is under way. Police have launched operations. We hope the attacker will be captured soon."
Police believed there was only one gunman, he said, although some eyewitness reports mentioned multiple attackers.
The Ministry of Foreign Affairs and Trade said there was no indication at this stage that any New Zealanders had been caught up in the massacre.
There are 109 New Zealanders registered as being in Turkey.
There has been widespread condemnation of the gun attack on hundreds of revellers celebrating New Year at a nightclub in Istanbul.
The Russian president, Vladimir Putin, said it was hard to imagine a more cynical crime and he promised to be a reliable partner to Turkey in the fight against terrorism.
He condemned the "cynical" murder of civilians. "Our shared duty is to decisively rebuff terrorist aggression," he said.
In the United States the White House condemned what it called a horrific terrorist attack.
US President Barack Obama, who is on holiday in Hawaii, offered condolences "for the innocent lives lost" and offered "appropriate assistance".
In Rome, Pope Francis urged people to combat the violence that, as he put it, covered the world with a shadow of fear and dismay.
Turkish prime minister Binali Yildirim said Turkey would not give into violence.
- BBC / RNZ