Pompeo calls for 'thorough' probe into Khashoggi's disappearance
"We call on the government of Saudi Arabia to support a thorough investigation of Mr Khashoggi's disappearance and to be transparent about the results of that investigation," Pompeo said in a statement, after President Trump voiced concern about his disappearance.
Khashoggi, 59, went to the consulate on Tuesday to obtain official documents ahead of his marriage to his Turkish fiancee.
Turkish police said he never left the building, and that a team of around 15 Saudi officials arrived on two flights on Tuesday and were at the consulate at the same time as Khashoggi.
"Based on their initial findings, the police believe that the journalist was killed by a team especially sent to Istanbul and who left the same day," a Turkish government source told AFP on Saturday.
Riyadh insists Khashoggi left the consulate, describing claims that he was killed there as "baseless".
"We have seen conflicting reports on the safety and whereabouts of prominent Saudi journalist and Washington Post contributor Jamal Khashoggi," Pompeo said.
State Department senior officials have spoken with Saudi Arabia through diplomatic channels about the matter, the top US diplomat added.
Khashoggi, a US resident for about the past year, has written articles critical of Saudi Crown Prince Mohammed bin Salman.
Reporters Without Borders (RSF) said on Twitter that if reports of Khashoggi's death were confirmed, "this would constitute a horrific, utterly deplorable, and absolutely unacceptable assault on press freedom".
Saudi Crown Prince Mohammed bin Salman has launched a fierce crackdown on opponents and critics of his de facto rule.
At least 11 journalists are currently being detained in Saudi Arabia and the kingdom ranks as one of the worst in the world when it comes to press freedom.
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