A member of the 15-man team suspected in the death of Jamal Khashoggi dressed up in his clothes and was captured on surveillance cameras around Istanbul on the day the journalist was killed, a senior Turkish official has told CNN.

CNN has obtained exclusive law enforcement surveillance footage, part of the Turkish government's investigation, that appears to show the man leaving the Saudi consulate by the back door, wearing Khashoggi's clothes, a fake beard, and glasses.

The same man was seen in Khashoggi's clothing, according to the Turkish case, at the city's world-famous Blue Mosque just hours after the journalist was last seen alive entering the consulate on October 2.

The man in the video, identified by the official as Mustafa al-Madani, was allegedly part of what investigators have said was a hit squad, sent to kill the journalist during a scheduled appointment to get papers for his upcoming wedding.

In the apparent cover-up that followed Khashoggi's death, Madani, 57, who is of similar height, age and build to Khashoggi, 59, was used as a decoy for the journalist, according to the Turkish official.

A senior Turkish official told CNN that the video showed that Madani was brought to Istanbul to act as a body double.

A Saudi source would not confirm or deny that Madani was sent to act as a body double, though he emphasized that the killing of Khashoggi was not intentional.

Madani, a decade older than the other members of the 15-man team, exited the consulate building by the back door along with an alleged accomplice. Madani was wearing what the video appears to show to be Khashoggi's dark blazer, gray shirt opened at the collar and trousers.

Four hours earlier Madani had entered the consulate by the front door, alongside an alleged accomplice. Saudi's forensic medicine chief Salah al-Tubaiqi, another key suspect who was identified using facial recognition analysis together with CNN's timeline of events that day, was also present.

The video appears to show Madani without a beard, wearing a blue and white checked shirt and dark blue trousers. When he exited the consulate dressed as Khashoggi, the video then appears to show him wearing the same dark pair of sneakers with white soles that he first arrived in prior to the journalist's death.

"Khashoggi's clothes were probably still warm when Madani put them on," the senior Turkish official told CNN.

•Madani at the Blue Mosque in Istanbul captured on law enforcement surveillance footage, according to a Turkish official.

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