CIA director Gina Haspel is due to brief President Trump on her visit to Turkey this week over the killing of Saudi journalist Jamal Khashoggi.
The meeting comes hours after media reports said that during the visit Ms Haspel had heard audio recordings that Turkey claims capture the murder.
Meanwhile Saudi Arabia’s public prosecutor was quoted as saying Khashoggi’s murder was “premeditated”.
The US-based Saudi government critic died in the consulate in Istanbul.
Saudi Arabia initially denied all knowledge of the writer’s whereabouts when he went missing on 2 October, but later admitted he was murdered at the Saudi consulate in Istanbul, blaming “rogue agents”.
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The official Saudi Press Agency reported that on Thursday Crown Prince Mohammed bin Salman chaired the first meeting of a committee to reform the state’s intelligence services, which was set up following Mr Khashoggi’s death.
Last week Saudi Arabia sacked two key advisers to the prince, and arrested 18 people.
On Thursday sources close to Khashoggi’s family said his eldest son Salah had left the country. He is reportedly on his way to the US.
Mr Khashoggi, who was filmed on Tuesday shaking hands with the crown prince, had previously been unable to leave because of a travel ban imposed because of his father’s criticism of the kingdom’s leadership.
What is Ms Haspel’s role?
The CIA director travelled to Turkey on Monday to review intelligence about the incident.
Reuters quoted White House spokeswoman Sarah Sanders as saying that Ms Haspel was scheduled to brief President Trump on the visit.
On Wednesday Turkey’s Sabah newspaper said she had listened to audio recordings of Khashoggi’s interrogation and death, but gave no details about the contents or how the audio had been obtained.
Now, sources quoted by the Washington Post and Reuters news agency have backed up the reports.
A person “familiar with the audio” told the Washington Post that it was “compelling”.
On Wednesday Saudi Crown Prince Mohammed bin Salman, who is regarded as the country’s de facto ruler, vowed to punish those responsible for the murder.
However, media reports have quoted Turkish security sources as saying the operation was run by a top aide to Prince Mohammed.
The crown prince was speaking at a business forum in Riyadh, dubbed “Davos in the Desert”, which has been boycotted by a number of political and corporate leaders.
What’s the latest with the investigation?
Turkey’s Anadolu news agency said on Thursday that 38 members of staff at the Istanbul consulate had been questioned as witnesses.
There is still no sign of the body.
The latest focus appears to be on a well in the garden of the Saudi consulate building.
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As with much of the investigation there have been conflicting reports. The Anadolu agency initially reported the Saudis had denied permission for it to be searched, only for broadcaster NTV to say later that permission had been given.
On Tuesday there were similar conflicting reports over whether Khashoggi’s belongings had been found in suitcases in a Saudi diplomatic car.
This week Turkish President Erdogan said Turkey had strong evidence the journalist was killed in a premeditated and “savage” murder and has called for the suspects to be tried in Istanbul.
What is Donald Trump’s line?
The case has strained Saudi Arabia’s relations with the US and other allies.
On Tuesday the US president voiced his strongest criticism of the Saudi government to date and suggested the crown prince must have known what was going on.
He told the Wall Street Journal: “Well, the prince [Mohammed bin Salman] is running things over there more so at this stage. He’s running things and so if anybody were going to be, it would be him.”
Earlier he said: “They had a very bad original concept, it was carried out poorly and the cover-up was the worst in the history of cover-ups.”
The US will revoked the visas of those believed responsible for Khashoggi’s killing – Saudi Arabia says 18 Saudi nationals have been detained.
How has the Saudi story changed?
First, Saudi Arabia said Khashoggi had left the building alive, then that he had been killed in a “fist-fight” inside the consulate.
It finally said that Khashoggi had been murdered in a “rogue operation” that the leadership had not been aware of.
An unnamed Saudi official told Reuters news agency on Sunday that Khashoggi had died in a chokehold after resisting attempts to return him to Saudi Arabia.
His body was then rolled in a rug and given to a local “co-operator” to dispose of, the official said.
- How Saudis changed story on Khashoggi