*Turkey vows to reveal all the details of a two-week inquiry
*Trump 'not satisfied with Saudi account of Khashoggi death'
*German Chancellor Merkel urged "transparency from Saudi"

Saudi Arabia admitted on Saturday that critic Jamal Khashoggi was killed inside its Istanbul consulate, but mystery surrounded the whereabouts of his body as Turkey kept up its investigation.

Ankara vowed it would reveal all the details of a two-week inquiry as international demands swirled for more answers over the death of the Washington Post columnist.

Before dawn yesterday, Riyadh backtracked on over a fortnight of denials by announcing that Khashoggi died during a "brawl" inside the consulate on October 2.

US President Donald Trump said yesterday that he is not satisfied with Saudi Arabia's explanation for the circumstances around the killing of Khashoggi.

Speaking to reporters in Nevada, Trump added that it was possible that Saudi Crown Prince Mohamed bin Salman had been unaware of the death.

Riyadh said 18 Saudis have been arrested in connection with his death and two top aides of the crown prince, as well as three other intelligence agents, have been sacked.

The mystery over the disappearance of Khashoggi, who was critical of the crown prince, plunged Saudi Arabia into an international crisis as the kingdom insisted for over two weeks that it was not involved.

Turkish officials have accused Riyadh of carrying out a state-sponsored killing and dismembering the body, which police have begun hunting for in an Istanbul forest.

In the latest version of events from Riyadh, Saudi Attorney General Sheikh Saud al-Mojeb said Khashoggi died after talks at the consulate degenerated into a physical altercation.

He did not disclose the whereabouts of the journalist's body.

"Discussions that took place between him and the persons who met him at the Saudi consulate in Istanbul led to a brawl and a fistfight with the citizen, Jamal Khashoggi, which led to his death, may his soul rest in peace," the attorney general said in a statement.

US President Donald Trump said he found the explanation credible despite continued scepticism from some US lawmakers, including Republicans.

The Saudi king also ordered the setting up of a ministerial body under the chairmanship of the crown prince to restructure the kingdom's intelligence agency and "define its powers precisely", Saudi state media said.

Key members of the crown prince's inner circle, deputy intelligence chief Ahmad al-Assiri and royal court media adviser Saud al-Qahtani, were sacked.

But Khashoggi's Turkish fiancee Hatice Cengiz tweeted that her heart was "full of sorrow" over the confirmation of his death.

The couple had been due to marry this month.

The controversy has put the kingdom — for decades a key ally in Western efforts to contain Iran — under unprecedented pressure.

It has evolved into a major crisis for Prince Mohamed, a Trump administration favourite widely known as MBS, whose image as a modernising Arab reformer has been gravely undermined.

Ankara said it regarded it as a "debt of honour" to reveal what happened.

"We are not accusing anyone in advance but we don't accept anything to remain covered (up)," said ruling Justice and Development Party spokesman Omer Celik.

Trump swiftly endorsed Saudi Arabia's explanation, calling it an "important first step".

"I do, I do," Trump said when asked if the Saudis' explanation was credible, while adding: "It's early, we haven't finished our review or investigation."

But there was a clamour for more answers and to bring those behind the killing to justice.

German Chancellor Angela Merkel urged "transparency from Saudi Arabia" and said that "available reports on what happened in the Istanbul consulate are insufficient".

French Foreign Minister Jean-Yves Le Drian said many questions remained "unanswered" and insisted "they require exhaustive and diligent investigation".

UN chief Antonio Guterres in a statement stressed "the need for a prompt, thorough and transparent investigation" and "full accountability for those responsible".

Britain's Foreign Office, which also has close ties to Riyadh, said it "was a terrible act and those responsible must be held to account".

Pro-government Turkish media have claimed that Khashoggi was tortured and dismembered by a Saudi hit squad, although Turkey has yet to release any official findings.

"Each successive narrative put out by the Saudis to explain what happened to Khashoggi has strained credulity," Kristian Ulrichsen, a fellow at Rice University's Baker Institute in the United States, told AFP.

"Especially because the Saudis are still unable or unwilling to produce the one piece of evidence — a body — that could provide a definitive answer one way or the other."

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