Acting on a tip-off, police raided an apartment in Istanbul's Zeytinburnu district but could not find the gunman who remains at large, Dogan news agency reported.
Islamic State (ISIS / Daesh / ISIL) claimed responsibility on Monday for a New Year's Day mass shooting in a packed Istanbul nightclub that killed 39 people, an attack carried out by a lone gunman who remains at large.
The attacker was believed to have taken a taxi from the southern Zeytinburnu district of Istanbul and, because of the busy traffic, got out and walked the last four minutes to the entrance of the nightclub, newspaper Haberturk said.
He pulled his Kalashnikov rifle from a suitcase at the side of the road, opened fire on those at the door, then threw two hand grenades after entering, Haberturk said, without citing its sources.
It said six empty magazines were found at the scene and that he was estimated to have fired at least 180 bullets.
Security services had been on alert across Europe for new year celebrations following an attack on a Christmas market in Berlin that killed 12 people.
Only days ago, an online message from a pro-Islamic State group called for attacks by "lone wolves" on "celebrations, gatherings and clubs".
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