Saudi State TV said 18 officials have been identified and detained in connection to the case.
The public prosecutor said Mr Khashoggi died after a fist fight in the consulate.
Saudi Arabia’s King Salman has fired deputy intelligence chief Ahmed Assiri and royal court adviser Saud al-Qahtani over Mr Khashoggi’s death.
Suspects linked to the death of the journalist will be held accountable and brought to justice, Saudi Arabia’s attorney general said.
Mr Khashoggi disappeared earlier this month when he was last seen entering the Saudi consulate in Turkey on October 2.
Turkish officials have since been scouring the nearby area for signs of his remains.
They have searched Belgrad Forest and neighbouring rural city, Yalova, as well as Turkish consulate buildings.
CCTV footage showed Mr Khashoggi entering the consulate as his finance was left outside.
More to follow…