Most of the dead in the attack were foreign nationals, mainly from the Middle East.

“The vile terrorist who attacked the place of entertainment on New Year’s Eve and led to the loss of so many lives has been captured,” Yildirim said.

He added: “What is important is for the suspect to be captured and for the forces behind it to be revealed.”

The premier wouldn’t provide further details on the arrest or the investigation, saying authorities would provide specifics “in time.”

Moments later in separate remarks, Istanbul governor Vasip Sahin said that the suspect is an Uzbekistan national who trained in Afghanistan. He is believed to have entered Turkey in January 2016. Sahin identified him as Abdulkadir Masharipov, saying he was born in 1983 without giving an exact birthday. Turkish media are reporting the suspect’s first name as Abdulgadir.

Sahin said that the man, captured late Monday, confessed to carrying out the massacre and that his fingerprints matched those of the attacker.

The suspect, according to Sahin, was a well-educated terrorist who speaks four languages and had clearly carried out the attack in the name of IS. He was operating under the alias “Ebu Muhammed Horasani”.

The police operation to apprehend him drew on the review of 7,200 hours of security camera footage and about 2,200 tipoffs from the public. Authorities seized nearly $200,000, two guns and two drones during the suspect’s arrest.

“Together with the terrorist, an Iraqi man was detained as well as three women from various countries — from Egypt and from Africa,” Sahin said.

“There is a high chance that they may be connected (to IS) because they were staying in the same house.”

The governor said it was believed that they arrived three days earlier at Esenyurt, an overall low-income neighbourhood of Istanbul that has witnessed a construction boom.

The state-run Anadolu Agency said that the gunman’s 4-year-old son was taken into protective custody.

Hurriyet newspaper earlier reported that the suspect’s wife and 1-year-old daughter were caught in a police operation in the neighbourhood of Zeytinburnu, a working class district of Istanbul, on January 12.

In another report citing police officials, the newspaper said the gunman had picked up his son from the working-class neighbourhood of Zeytinburnu after attacking the nightclub.

Sahin said the boy wasn’t with the gunman on the night of the police operation, although he had taken the child with him and left his daughter with his wife.

IS has claimed responsibility for the nightclub massacre, saying the attack in the first hours of Jan. 1 was in reprisal for Turkish military operations in northern Syria. The man identified as the suspect had been on the run since the attack.

Anadolu said police have also carried out raids on members of a suspected Uzbek IS cell in five Istanbul neighbourhoods, and detained several people.

Photographs from raids, widely published in the Turkish media, showed a bruised, black-haired man in a gray, bloodied shirt being held by his neck. NTV television said the gunman had resisted arrest.

Turkish media also circulated a photograph of the suspect lying on the floor facedown, hands bound behind his back with the boot of an unidentified man pressed to the back of his head.

At least 35 people have been detained before the latest raid in connection with the attack, according to Anadolu.

The Istanbul attack was the latest in which Uygurs have been involved in the past years, including a deadly bombing in a shrine in Bangkok in Thailand in September in 2015, a car bombing on the Chinese embassy in Bishkek, Kyrgyzstan in August.

“The Istanbul attack indicated that terrorists from the East Turkestan Islamic Movement (ETIM), who have posed threats to China, have also become a part of the global threat after its members joined the Islamic State,” said Li Wei, a counter-terrorism expert at the Anti-terrorism Studies Centre at the China Institute of Contemporary International Relations.

Additional reporting by Lara Zhou