The attack killed 39 people and injured 70 others at an Istanbul nightclub on New Year's Eve
The Islamic State (IS) group on Monday claimed responsibility for an attack on New Year's night in which a gunman opened fire inside a glamorous Istanbul nightclub, killing 39 people.
In a statement circulated on social media, the militant group said one of the "soldiers of the caliphate" had carried out the attack on the Reina nightclub in central Istanbul, leading some terrified partygoers to seek escape by jumping into the Bosphorus River.
Following the news, Istanbul's anti-terror police detained eight people suspected of links to the attack, a report said.
People lay flowers in front of the Reina night on 1 January in Istanbul, after a gunman killed 39 people (AFP)
The Dogan news agency said police were pressing on with operations after making the first arrests over the attack. The suspected gunman is still believed to be on the run.
Families are still due to reclaim the bodies of over two dozen non-Turkish nationals killed in the gun attack.
The attack - which unleashed scenes of carnage and panic among party-goers at one of Istanbul's swankiest venues - took place just 75 minutes into 2017, after a bloody year in which hundreds were killed in violence blamed on both IS militants and Kurdish militants.
Arriving by taxi at the plush Reina nightclub on the shores of the Bosphorus, the gunman produced a weapon, reportedly a Kalashnikov, and shot dead a policeman and civilian at the entrance.
According to the Hurriyet daily, the gunman then fired four magazines containing a total of 120 bullets around the club, as terrified guests flung themselves into the freezing waters of the Bosphorus in panic.
But after changing clothes, the gunman left the nightclub and has so far managed to evade the security forces.
Interior Minister Suleyman Soylu said Sunday that intense efforts were under way to find the gunman, and expressed hope that the suspect would be captured soon.
Late on Sunday, police rushed to the city's Kurucesme district after a tip-off, but the operation did not produce any arrest.
"The danger continues," wrote columnist Abdulkadir Selvi in Hurriyet.
"So long as this terrorist is not seized we do not know when and where a massacre could take place."
Attack aimed to sow 'chaos'
Before IS claimed responsibility, Turkish daily Hurriyet said authorities believed the attacker could be linked to the group, and may be from the Central Asian states of Kyrgyzstan or Uzbekistan.
Investigators are also probing whether the attacker is linked to the same cell that in June carried out a triple suicide bombing and gun attack at Istanbul's Ataturk airport blamed on IS that left 47 dead, it added.
Turkey also received intelligence from the United States on 30 December warning of the risk of attacks by IS in Istanbul and Ankara on New Year's night.
However, the intelligence did not specify where such an attack could take place, the article added.
So far, officials have not confirmed the IS claim of responsibility for the latest carnage.
The attack comes as Turkish troops press a four-month incursion in Syria to oust IS militants and Kurdish militants from the border area.
President Recep Tayyip Erdogan, who said the nightclub bloodbath sought to sow "chaos," was on Monday due to chair a meeting of the Turkish cabinet at his presidential palace in Ankara.
Prime Minister Binali Yildirim meanwhile denied earlier reports that the attacker had worn a Santa Claus costume.
Soylu said the gunman had arrived with a gun concealed under an overcoat but subsequently exited the venue wearing a different garment.
NTV television said that the bodies of 25 foreigners killed in the attack were to be handed back to their families on Monday following identification.
According to Turkish press reports, the latest figures show 11 Turks were killed in the attack alongside 27 foreigners, including one Belgian-Turkish dual national. One victim is still unidentified.
Sixty-five people were wounded in the attack.
The foreigners who died - most of them from Arab countries - had come to the club to celebrate a special night in style.
'Around 1.15 am, we heard Kalashnikov fire. We thought it might be people who had drunk too much and were fighting, but then people started throwing themselves to the ground'
- Albert Farhat
They included three Lebanese nationals, two Jordanians and three Iraqis, officials in the respective countries said.
A Canadian woman and a teenage women, a Palestinian citizen of Israel, were also among dead. Turkish press reports said at least seven Saudi nationals died but this has yet to be confirmed by Riyadh.
Speaking to Lebanese TV station LBCI, Albert Farhat recalled how the attack began.
"Around 1.15 am, we heard Kalashnikov fire. We thought it might be people who had drunk too much and were fighting, but then people started throwing themselves to the ground," he said.
The attack evoked memories of the November 2015 carnage in Paris when IS militants unleashed a gun and bombing rampage on nightspots in the French capital, killing 130 people including 90 at the Bataclan concert hall.
World leaders rushed to condemn the nightclub shooting, with Russian President Vladimir Putin saying it was "hard to imagine a crime more cynical than the killing of civilians during a New Year's celebration".