ISTANBUL - Saudi Arabia’s ambassador to Turkey was summoned to the foreign ministry after a prominent journalist critical of Riyadh went missing, a Turkish diplomatic source said on Thursday.

Jamal Khashoggi, a contributor to the Washington Post, went to the Saudi consulate on Tuesday to receive an official document for his marriage and has not appeared since. His Turkish fiancee reported him missing after Khashoggi, who has lived in self-imposed exile in the United States since last year to avoid possible arrest, did not emerge from the consulate.

The Saudi ambassador was received by Turkish Deputy Foreign Minister Yavuz Selim Kiran on Wednesday, the diplomatic source and state-run news agency Anadolu said. After an initial period of silence, Saudi Arabia said the consulate was working with Turkish authorities “to uncover the circumstances of the disappearance of Jamal Khashoggi after he left the consulate building”.

Turkish presidential spokesman Ibrahim Kalin however told reporters on Wednesday the journalist was being held at the consulate, adding that Ankara was in touch with Saudi officials.

“According to information we have, this individual who is a Saudi national is still at the Istanbul consulate of Saudi Arabia,” Kalin said.

The journalist, who writes opinion pieces for the Post, has been critical of some policies of Saudi Crown Prince Mohammed bin Salman and Riyadh’s intervention in the war in Yemen.

US officials said they were looking into his case.

Khashoggi’s fiancee Hatice, 36, told AFP on Thursday that there had been no news about him.

“We don’t know where he is. If he had left the consulate as said by the Saudis, we would know where he is,” she said.

Khashoggi, who turns 60 on October 13, had previously served as an adviser to the Saudi government.