A source close to the investigation told Sky News the police and intelligence services:
:: Tried to set up roadblocks
:: Put out a call to the airport to stop them at passport control
:: Searched one of the jets taking the team back to Saudi Arabia
A picture is emerging of a dramatic scramble to try to stop the men believed to be responsible for the disappearance of Jamal Khashoggi.
The journalist hasn‘t been seen since he entered the consulate on 2 October to get marriage papers.
Image: Jamal Khashoggi was last seen on 2 October
But even though the alarm was raised within hours by the journalist‘s fiancee who was waiting outside the consulate, it proved too late.
The journalist‘s fiancee, Hatice Cengiz, rang one of the president‘s advisers as well as a close journalist friend.
Politicians at the head of the Turkish government were alerted, as well as police and intelligence services – and as many of them had diplomatic status, it is thought they went through a VIP section of the airport and managed to slip away.
Image: Mr Khashoggi's fiancee Hatice alerted authorities when Mr Khashoggi failed to come out
Two private jets were used to ferry the team back to Saudi Arabia.
Police managed to board at least one of the jets posing as cleaners but found nothing.
Investigators speaking anonymously through a number of different media channels including Sky News are insistent they have an audio recording documenting the journalist‘s beating and death shortly after he turned up at the Saudi consulate.
They also insist they have not shared it with anyone outside Turkish intelligence.
1:07 Video: 'Hit squad member' seen at Saudi consulate
Reports through US media that the recording was played to US secretary of state Mike Pompeo have been denied by the man himself.
If the recording is as strong as the Turks say it is, it would be difficult for Mr Pompeo to admit hearing it and still maintain any sort of diplomatic position with Saudi Arabia.
One of Mr Khashoggi‘s closest friends and the same man his fiancee rang for help when the journalist did not emerge from the consulate spoke to Sky News about his disgust at the idea of any cover-up.
“If nothing is done, then everyone in the world will know, no one is safe, even if you go into a consulate,” Turan Kislakci said from his office in Istanbul.
Istanbul‘s chief prosecutor has subpoenaed all the Turkish staff working at the consulate including cleaners, maintenance workers, the consul general‘s driver and the telephone operator.
The investigators have also searched Belgrade Forest in Istanbul after tracking two vehicles they believe were used in the attempt to cover up the journalist‘s killing.
They have also collected samples from both the consulate and the nearby consul general‘s home to try to match with Mr Khashoggi‘s DNA.
One former ambassador and an expert on US-Turkish relations told us it was inconceivable that the Saudi royal circle did not know about the killing.
Matthew Bryza, the former US ambassador to Azerbaijan, told Sky News there was no way a 15-person team could enter a consulate and beat and kill a man without clearance from seniors.
Intelligence sources have told Sky News they believe there was an attempt to destroy evidence and either deliberately or while shifting the remains, the journalist‘s remains have been spread in several different places.