Transcript for Missing journalist critical of Arab governments in final column

The latest on that deepening crisis over the missing "Washington post" columnist apparently murdered inside the Saudi consulate in istanbul. His final op-ed published overnight as we learn new details about what may have happened. ABC's Ian Pannell is there in istanbul with the latest. Good morning, Ian. Reporter: Yeah, robin, good morning. What the Arab world needs most is free expression. That's the prescient haunting title to an editorial by Jamal khashoggi published in morning in "The Washington post." One of his closest friends speaking to ABC in his first sit-down interview with U.S. Media revealing detailsment as the world searches for an answer, what looks like his final work published overnight in "The Washington post." His editors saying we held off hoping Jamal would come back to us. In it khashoggi urges readers to understand the need for freedom of expression in the middle East. The Arab world facing its own version of an iron curtain imposed not by external actors but through domestic forces vying for power and remains critical of Arab governments as intolerant of criticism. Arab governments have been given free rein to continue silencing the media at an increasing rate. Chilling words seemingly from beyond the grave. The kind of words that may have cost him his life. One of khashoggi's closest friends, turan kislakci, telling us overnight that the Saudis not only killed him in the consulate but in a terrible way. He describes what he was told in multiple briefings by Turkish security officials. They told me directly, djalilov had been killed using a barbaric method and this was on the audio recording. Kislakci says those audiotapes reveal that when khashoggi walked into the consulate he was given a document to sign. He refused and was then killed. Turkish forensic investigators have been combing through the grounds in recent days. Turkish sources releasing images of 15 Saudis they say traveled here to istanbul the day the journalist went missing. According to "The New York Times" among the suspects an autopsy expert, the times also reports several of the suspects have ties to the Saudi crown prince like this man, mutreb seen within a few feet of the crown prince earlier this year. Another photo of the man in Houston and another traveling together in Madrid. As for khashoggi's closest friend, he says he's in shock. "Jamal did not deserve this and no person ever deserves such a death, not even if he were the most extreme adversary." Well, meanwhile, investigators finishing looking over the consul general's office taking away a vast amount of material and awaiting the results of that examination. Robin. We are, all right, Ian, thank you.

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