Turkish police have apprehended a suspected organizer of the January 16 attack that killed at least 39 people at an Istanbul nightclub, Turkish media reports said.
Reports cited Turkish prosecutors as saying on February 14 that a French citizen of Turkish origin had been detained in Istanbul on February 12.
Authorities say the suspect, identified only as A.S., is believed to be one of the organizers of the attack.
At least 39 people were killed and 65 others were wounded when a gunman opened fire on New Year's revelers in the nightclub early on January 1.
The suspected shooter, Uzbek national Abdulkadir Masharipov, was detained in Istanbul on January 16.
The extremist group Islamic State (IS) claimed responsibility the day after the attack, calling it revenge for Turkey's military involvement in Syria.