Turkish prosecutors have opened an investigation into the disappearance of a missing Saudi journalist.
Jamal Khashoggi, a critic of Saudi Arabia’s Crown Prince Mohammed bin Salman, has not been seen since Tuesday, when he entered the Saudi consulate in Istanbul.
Turkish officials have said they believe Mr Khashoggi is still inside.
Prince bin Salman told Bloomberg News Turkish authorities were welcome to search the building.
What is Turkey doing?
Turkish media said prosecutors were now looking closely at the case, although this may be a widening of an inquiry begun on Tuesday.
Reuters quoted the Turkish ruling party as saying the investigation would be comprehensive and that the government’s sensitivity about the case was at the “highest level”. The AK Party said Mr Khashoggi’s whereabouts would be uncovered.
The head of the Turkish-Arab Media Association told the New York Times earlier that Turkish police officers providing security for the consulate had checked their security cameras and did not see the journalist leave on foot. But Turan Kislakci added that diplomatic cars had been seen moving in and out.
On Wednesday, the Turkish foreign ministry summoned Saudi Arabia’s ambassador and asked for an explanation about the disappearance.
The BBC’s Mark Lowen says the mystery threatens to deepen the strains in the relationship between Turkey and Saudi Arabia.
Turkey has taken the side of Qatar over its blockade by Saudi Arabia and other neighbours, and Turkey’s rapprochement with Iran has riled the government in Riyadh, our correspondent adds.
What have the Saudis said?
Prince bin Salman told Bloomberg: “He’s a Saudi citizen and we are very keen to know what happened to him. And we will continue our dialogue with the Turkish government to see what happened to Jamal there.
“My understanding is he entered and he got out after a few minutes or one hour. I’m not sure. We are investigating this through the foreign ministry to see exactly what happened at that time.
“The premises are sovereign territory, but we will allow them to enter and search and do whatever they want to do. If they ask for that, of course, we will allow them. We have nothing to hide,” Mr bin Salman said.
When asked if Mr Khashoggi faced charges in Saudi Arabia, the crown prince said his country would need to know where he was first.
What happened on Tuesday?
Mr Khashoggi went to the consulate to obtain a document certifying he had divorced his ex-wife, so that he could marry his Turkish fiancée, Hatice, who went with him to the building and waited outside, but did not see him leave.
She said that he was “stressed and sad” that he was forced to go to the building.
He was required to surrender his mobile phone, which is standard practice in some diplomatic missions.
Hatice said he left the phone with her and told her to call an adviser to Turkish President Recep Tayyip Erdogan if he did not return.
She said she waited for him outside the consulate from about 13:00 (10:00 GMT) until after midnight and did not see him leave. She returned when the consulate reopened on Wednesday morning.