Turkish police have found evidence suggesting Jamal Khashoggi was murdered inside the Saudi consulate in Istanbul but disclosed no further details, according to the Associated Press.

The purported evidence was found despite a declaration by Turkey’s president that Saudi operatives may have painted over crucial evidence at the consulate.

A Turkish Foreign Ministry official confirmed the Saudi consul’s home in Istanbul is going to be searched. Investigators who inspected the consulate on Monday found toxic materials, President Recep Tayyip Erdogan has said. The consul general himself, Mohammad al-Otaibi, has left Turkey. It is not clear if his departure was routine or whether he had been declared persona non grata by Turkish officials.

The developments in the fast-moving case came as US Secretary of State Mike Pompeo met with Saudi officials in Riyadh over Mr Khashoggi’s fate.

Mr Khashoggi’s disappearance ignited a global political and diplomatic uproar. Turkish officials confirmed he was coming to Turkey after meeting with officials that included a chummy sitdown with Saudi’s controversial crown prince, Mohammed bin Salman, the kingdom’s de facto ruler and the alleged mastermind behind Mr Khashoggi’s disappearance.

Mr Pompeo met with King Salman and then Crown Prince Mohammed bin Salman, who said of the relationship with the US: “We are strong and old allies. We face our challenges together – the past ... tomorrow.”

CNN and other news outlets cited anonymous sources saying the Saudis may admit culpability for The Washington Post columnist’s fate – presumed to be murder – but describe it as an unauthorised rendition attempt gone wrong. Saudi officials have not commented on the reports, and have continued to insist that Mr Khashoggi walked out of the consulate shortly after arriving.

A joint team of Saudi and Turkish investigators and officials swarmed into the consulate Monday evening in a possible attempt to examine the facility for traces Mr Khashoggi.

Mr Erdogan, speaking to reporters in parliament on Tuesday, raised the possibility that parts of the consulate had been repainted.

The investigation is looking into many things such as toxic materials and those materials being removed by painting them over Turkish president, Recep Tayyip Erdogan

“The investigation is looking into many things such as toxic materials and those materials being removed by painting them over,” he said.

The family of Mr Khashoggi released a statement calling for an international inquiry into his disappearance, saying they were in contact with him just before he entered the consulate on 2 October and vanished.

“We are sadly and anxiously following the conflicting news regarding the fate of our father after losing contact with him two weeks ago, when he disappeared after entering the Saudi consulate in Istanbul,” said the statement.

“Our family is traumatised, and yearns to be together during this painful time. The strong moral and legal responsibility which our father instilled in us obliges us to call for the establishment of an independent and impartial international commission to inquire into the circumstances of his death.”

Donald Trump says Jamal Khashoggi could have been work of 'rogue killers'

Diplomatic missions across the world are often treated like foreign soil, enjoying immunity from local laws.

The UN human rights chief Michelle Bachelet on Tuesday called on Riyadh to waive its rights on its diplomatic missions in Istanbul and give Turkish authorities access to all properties and staff. She called on both Riyadh and Ankara to publicly disclose all the information they had gathered about Mr Khashoggi’s disappearance.

The residence of the Saudi consul general, located north of the consulate where Mr Khashoggi was last spotted entering by security camera footage leaked to Turkish and international media, may be a key element in the investigation.