A defector from the Islamic State terror group spoke to Sky News about how militants prepared captives for executions and how the militant known as "Jihadi John" gave orders.
"Turkish man say, 'Put this camera there, change place there,' but John [was] the big boss," the defector in Turkey said of Mohammed Emwazi, the 26-year-old Londoner featured in videos sent out by the Islamic State, also known as ISIS or ISIL. "All time, all time say to all 'fastly, fastly, fastly, we should finish.' So respect him. Only he talks orders — others do."
The jihadist group reportedly staged mock executions to prepare hostages for being on camera, telling them in the rehearsals that they would not be harmed.
Sky reports: "The execution rehearsals took place so that when the moment of death finally came, the hostages were not expecting to be killed and were relaxed to appeal for their release on camera."
The hostage-beheading videos have become an important part of ISIS propaganda. The videos attract attention by the news media and are accessible to the world through YouTube and other video-hosting sites.
Sky's source, who goes by the pseudonym "Saleh," said he was a translator for ISIS. He reportedly fled to Turkey to escape the group.
The man said that "John," recently identified as Emwazi, was the group's chief killer of foreign hostages.
Saleh said his job was to help convince the hostages they were safe.
Emwazi "would say to me, 'Say to them, no problem, only video, we don't kill you, we want from your government [to] stop attacking Syria. We don't have any problem with you; you are only our visitors,'" Saleh told Sky, adding that he knew the whole time the hostages would eventually be killed.
The hostages were also reportedly encouraged to become Muslim and given Arabic names to help them feel more relaxed among the militants.
Saleh's statements are in line with what a former CIA counterterrorism analyst wrote for The Washington Post in September. Seeking to explain the hostages' calm demeanor in ISIS' videos, Aki Peritz suggested they might not have known they were to be killed. And statements from former ISIS hostages have corroborated the mock-execution story.
Emwazi reportedly left Europe for Syria in 2012 and is believed to be responsible for multiple executions of Western hostages.