Turkish media outlets have aired CCTV footage of what they purport to be a 15-member Saudi Arabian “assassination squad” linked to the disappearance of journalist Jamal Khashoggi.

Mr Khashoggi, a US-based Saudi national, was last seen a week ago entering the Saudi consulate in Istanbul to get documents related to his forthcoming marriage.

His Turkish fiancee, Hatice Cengiz, was waiting outside the building and said he never re-emerged.

Turkish officials have been quoted as saying they believe Mr Khashoggi, a prominent critic of Saudi policies, was killed inside the mission.

On Thursday morning (AEST), the The New York Times quoted highly placed Turkish security sources as saying that Mr Khashoggi was killed within hours of entering the consulate by a special hit squad on the orders of the Saudi royal court, and that his body had been dismembered with a bone saw.

“It is like Pulp Fiction,” an official told the Times.

The images and video released by Turkish media show alleged suspicious movements at the Saudi Consulate in Istanbul following Mr Khashoggi’s disappearance a week ago.

Saudi Arabia, which has dismissed as baseless accusations that it killed or abducted Mr Khashoggi, remained silent as the images were broadcast across television networks in Turkey and around the world.

A critic of Crown Prince Mohammed bin Salman, Mr Khashoggi was living in self-imposed exile in the US where he wrote for the Washington Post.

Once seen as a Saudi royal insider, he previously served as an adviser to senior Saudi officials.

Turkey’s Sabah newspaper published the names and years of birth of 15 Saudis it said arrived at Istanbul’s Ataturk airport on October 2. Twelve of the Saudis allegedly arrived early that day, based on photos captured at passport control which it published.

The 15 departed at four different times, Sabah reported.

Turkish NTV broadcast videos of what it said were the men arriving at the airport and checking into one hotel, as well as videos of what it said was a large van arriving at the consul general’s residence two hours after Mr Khashoggi had entered the consulate.

US President Donald Trump on Thursday morning condemned the disappearance.

“We cannot let this happen to reporters, to anybody,” he told media, adding that the situation was “serious”.

Mr Trump invited Mr Khashoggi’s fiancée to the White House.

Secretary of State Mike Pompeo and other top US officials have spoken with Prince Mohammed Bin Salman about Mr Khashoggi’s disappearance.

A White House statement said the officials “asked for more details and for the Saudi government to be transparent in the investigation process”.

-with agencies