Tun farko kafofin yada labarai na Turkiya sun ce hukumomi sun yi imanin kungiyar IS mai ikirarin neman kafa daular Islama tana da hannu wajen kai harin na Santanbul, kuma akwai yuwuwar dan bindigan ya fito ne daga kasashen tsakiyar Asiya, tsakanin Uzbekistan ko kuma Kyrgyzstan.
