Turkey opens probe over missing Saudi journalist Jamal Khashoggi

Turkey has opened an investigation into the case of the missing Saudi journalist Jamal Khashoggi, who has not been seen since going to the Saudi consulate in Istanbul four days ago, Turkey's Anadolu Agency reported on Saturday.

Khashoggi, a Washington Post columnist and outspoken critic of the Saudi government, went into the consulate on Tuesday to pick up documents relating to his divorce and has not been seen since. 

Riyadh denies claims that it has detained Khashoggi and said the journalist left the consulate soon after. 

Police, cited by Anadolu, said that Khashoggi "did not come back out" of the consulate after entering the building.

The police said about 15 Saudis, including officials, came to Istanbul on two flights on Tuesday and were at the consulate at the same time as the journalist. They left again the same day, police added.

The news agency cited Istanbul prosecutors as saying that an investigation had been launched on Tuesday and had been widened since.

Saudi Arabia's ambassador was summoned to the foreign ministry on Thursday, the Daily Sabah said. Ambassador Waleed AM Elkhereiji was asked about Khashoggi in a meeting with Deputy Foreign Minister Yavuz Selim Kiran.

A former government adviser who has been critical of some policies of Saudi Crown Prince Mohammed bin Salman and Riyadh's intervention in the war in Yemen, Khashoggi has lived in self-imposed exile in the United States since last year to avoid possible arrest.

The Saudi crown prince told Bloomberg on Friday that the journalist was not inside the consulate and said he was ready to allow Turkish authorities to search the building.

"We are ready to welcome the Turkish government to go and search our premises," he said, which is Saudi sovereign territory.

"We will allow them to enter and search and do whatever they want to do... We have nothing to hide."

According to Khashoggi's fiancee, a Turkish woman identified only as Hatice A, Khashoggi went to the consulate to receive an official document regarding his marriage and never re-emerged.