He reportedly carried an AKM rifle; after killing a police officer and a bystander at the entrance he entered the club shooting, allegedly dressed up as Santa Claus.

[35] Masharipov was 28 years old at the time of the attack and is believed to have been trained as a militant in Afghanistan and Pakistan before illegally entering Turkey through the Iranian border in January 2016.

[35] Masharipov is also believed to have trained with Al Qaeda in Iraq, the group that morphed into ISIL, and had spent most of his time in Turkey in the city of Konya before arriving in Istanbul on 16 December 2016.

[35][36] In an interview with police, Masharipov stated he was initially directed by ISIL to stage an attack at Taksim Square, but dropped the plan after conducting surveillance of the area and concluding there was too much security.

[36] In September 2020, a Turkish court sentenced Masharipov to life imprisonment, plus an additional 1,368 years in prison, for killing 39 people and injuring 79 more.

[60] The President of Turkey Recep Tayyip Erdoğan condemned the attack and offered condolences on behalf of those who died, including victims from other countries.

[63][64] Some Turkish citizens, journalists, and pro-AKP journals such as Sabah put forward conspiracy theories claiming that agencies from Western countries, such as the CIA, organized the attack.

[66] Doğu Türkistan Bülteni Haber Ajansı, speaking on behalf of the TIP, pledged its animosity against Russia and the PKK, saying it fought them alongside Turkmen in Syria for six years, denying involvement in the Reina nightclub massacre and trying to blame China for the massacre, claiming that Uyghurs in Küçükçekmece and Zeytinburnu were being unfairly targeted.

[67] Doğu Türkistan Bülteni Haber Ajansı and Zeytinburnu Uyghurs blamed the Gülen movement for the Reina nightclub massacre.