Turkish media has shown footage of the house where the man accused of carrying out the Reina nightclub attack was arrested.
Images from inside the house, which is reported as being in the city's Esenyurt district, show a broken door and dirty kitchen.
Police sources say that since the attack in the early hours of New Year's Day the suspect, named as Abdulkadir Masharipov, never left Istanbul.
But he is thought to have changed locations within the city several times ahead of his arrest.
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