The killing of Khashoggi, a Washington Post columnist and a critic of Saudi Arabia's de facto ruler, Crown Prince Mohammed bin Salman, has sparked global condemnation and mushroomed into a major crisis for the world's top oil exporter.
Saudi Arabia first denied any role in Khashoggi's disappearance before blaming his Oct. 2 death at the Saudi consulate in Istanbul on a botched attempt to return him to the kingdom.
On Thursday, Saudi state Ekhbariya TV quoted the Saudi public prosecutor as saying Khashoggi's murder was premeditated, and that prosecutors were interrogating suspects on the basis of information provided by a joint Saudi-Turkish task force.
Turkey has dismissed Saudi efforts to blame rogue operatives and urged the kingdom to search from "top to bottom" for those responsible for the killing of Khashoggi, a Washington Post columnist and critic of the Saudi leadership.