DOZENS of people have been killed as they celebrated New Year at a Turkish nightclub in a suspected terror attack.
Officials said two and perhaps three gunmen, reportedly wearing Santa Claus costumes, murdered a police officer and a civilian outside Istanbul's famed Reina nightclub before bursting inside.
The attackers opened fire into the crowd of up to 700 people, killing at least 35 and injuring dozens more, including foreign nationals.
Reports said some people jumped into the waters of the Bosphorus Strait to escape the massacre, which started shortly before 1.30am local time.
Turkish media outlets said one attacker was believed to have been killed at the scene and the other suspects were thought to have fled.
CCTV footage from inside the club was broadcast by Turkish media, appearing to show a gunman dressed as Father Christmas walking through abandoned drinks booths.
One survivor said she had to climb out from beneath bodies inside the nightclub to flee the attack, where her husband was injured.
"Before I could understand what was happening, my husband fell on top me,” Sinem Uyanik told the Associated Press outside Istanbul's Sisli Hospital.
"I had to lift several bodies from on top of me before I could get out.”
Governor of Istanbul, Vasip Sahin, described the event as a "terror attack” but did not name who he thought responsible.
He said one police officer was among those killed by a long-barrelled weapon, with 40 others taken to hospital for treatment.
"The attacker - in the most brutal and merciless way - targeted innocent people who had only come here to celebrate the New Year and have fun,” Mr Sahin said.
Armed police blocked off the area as the roads were lined with dozens of ambulances, with well-dressed clubbers pouring into the street.
Security in Turkish cities had been heightened for New Year's Eve, with 17,000 police officers including some camouflaged as Santa Claus, on duty in Istanbul, according to the state-run Anadolu news agency.
The latest attack came at the end of a bloody year in Turkey, where terror attacks by Islamic State and Kurdish extremist groups inflicted a death toll of more than 180.
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