Slideshow ( 2 images )

ISTANBUL (Reuters) - A Turkish court on Saturday remanded in custody an Uzbek national accused of killing 39 people in an Istanbul nightclub on New Year’s Day, state-run media said, an attack the authorities blamed on Islamic State.

Abdulgadir Masharipov, who was caught in a police raid in Istanbul on Jan. 16, was formally charged with membership of an armed terrorist group, multiple counts of murder, possession of heavy weapons and attempting to overturn the constitutional order, the state-run Anadolu news agency said.

Islamic State claimed responsibility a day after the mass shooting at the exclusive Reina nightclub on the shores of the Bosphorus waterway, saying it was revenge for Turkish military involvement in Syria.

NATO member Turkey is part of the U.S.-led coalition against Islamic State and launched an incursion into neighboring Syria in August to drive the Sunni militants, and Kurdish militia fighters, away from its borders.

The jihadist group has been blamed for at least half a dozen attacks on civilian targets in Turkey over the past 18 months, prompting the authorities to intensify their efforts to break up its suspected networks in the country.

Police in the southern city of Adana detained a Danish and a Swedish citizen suspected of receiving weapons and explosives training in Syria and of planning attacks in Europe, Anadolu said on Saturday.

On Thursday, police in Gaziantep, another city near the Syrian border, detained four Islamic State suspects believed to be planning attacks in Turkey, along with suicide belts and explosives.

The arrests came after the biggest round-up targeting the jihadist group in Turkey last weekend, in which 748 suspects were detained.