At least 39 people, including 16 foreigners, have died in an attack on a nightclub in Istanbul, Turkey’s interior minister has said.
Suleyman Soylu also revealed police were still hunting for the “terrorist” who attacked the Reina nightclub at about 01:30 local time.
For hours after the attack the authorities had said nothing about the whereabouts of the assailant.
Another 69 people were being treated in hospital, the minister added.
“The search for the terrorist continues… I hope (the attacker) will be captured quickly, God willing,” Mr Soylu said.
The Turkish authorities have imposed a media blackout on coverage of the attack, but it does not extend to official statements.
Istanbul governor Vasip Sahin earlier revealed a police officer had died in the attack.
One attacker was involved, the governor said, while CNN Turk reported he was dressed in a Santa Claus costume.
“A terrorist with a long-range weapon … brutally and savagely carried out this incident by firing bullets on innocent people who were there solely to celebrate the New Year and have fun,” Mr Sahin told reporters at the scene of the upmarket Reina nightclub in the the Ortakoy area on the banks of Bosphorus.
The club was popular not only with Turks, but with foreigners as well, according to the BBC’s Selin Girit in Istanbul.
She added some eyewitnesses spoke of there being not one but two attackers.
There were reportedly as many as 700 people in the nightclub at the time of the attack, some of whom have jumped into the water to escape.
Dogan news agency reported that some witnesses claimed the attackers were “speaking Arabic” while Turkish television channel NTV said special force police officers were searching the nightclub.
US President Barack Obama, who is on holiday in Hawaii, was among the first international leaders to make a statement after being briefed by his team.
“The president expressed condolences for the innocent lives lost, directed his team to offer appropriate assistance to the Turkish authorities, as necessary, and keep him updated as warranted,” White House spokesman Eric Schultz said in a statement.
The Turkish government has ordered a temporary media blackout in the wake of the attack, citing security and public order concerns.
This is not the first time such an order has been made.
Istanbul was already on high alert with some 17,000 police officers on duty in the city, following a string of terror attacks in recent months.
Many were carried out by so-called Islamic State (IS) or Kurdish militants.
Less than a fortnight ago, the Russian ambassador, Andrei Karlov, was shot dead by off-duty Turkish policeman Mevlut Mert Altintas as he gave a speech in the capital Ankara in December.
After the shooting, the killer shouted the murder was in revenge for Russian involvement in the conflict in the Syrian city of Aleppo.
Deadly attacks in Turkey in 2016
10 December: Twin bomb attack outside a football stadium in Istanbul kills 44 people, Kurdish militant group claims responsibility
20 August: Bomb attack on wedding party in Gaziantep kills at least 30 people, IS suspected
30 July: 35 Kurdish fighters try to storm a military base and are killed by the Turkish army
28 June: A gun and bomb attack on Ataturk airport in Istanbul kills 41 people, in an attack blamed on IS militants
13 March: 37 people are killed by Kurdish militants in a suicide car bombing in Ankara
17 February: 28 people die in an attack on a military convoy in Ankara