Jihadi John Mohammed Emwazi
IS defector reveals Mohammed Emwazi aka Jihadi John subjected hostages to mock executions University of Westminster/YouTube

Islamic State's (Isis) celebrity butcher Jihadi John subjected hostages to mock executions and possesses powerful charisma among fellow fanatics, a defector has revealed.

Speaking to Sky News, a former fighter for IS who was present at the murder of Japanese prisoner Kenji Goto shed light on how the staged murders unfolded.

The former translator named Saleh recounted his conversations with Jihadi John – aka 26-year-old Mohammed Emwazi – a former London resident who studied computers at university.

Using broken English, Saleh said: "He [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'.

"So they don't worry. Always I say to them 'don't worry, doesn't matter, nothing dangerous for you. But at the end I was sure [they would die]."

Mock executions were also performed meaning the victims were used to the procedure. Combined with lies told to hostages in the moments before they were brutally murdered, it helps explain why captives appeared calm.

Saleh revealed the aftermath of Goto's murder, which was performed on camera for propaganda reasons by the Islamist group. The translator said the episode underlined for him how high Emwazi's regard was within IS.

"After he was killed him, three or four person come and take over the body and put in a car. After that, John went on a different road.

"The big boss was there with them. Turkish man say 'put this camera there, change place there' but [Jihadi] John [was] the big boss. All time, all time say to all 'fastly, fastly, fastly, we should finish'. So respect him."

Emwazi commands respect among fellow fanatics because he is willing to take the step of murdering foreigners on camera - something which fellow fighters are reluctant to do, Saleh said.

"Maybe because he use the knife," he said. "I cannot understand why he is so strong. One man can kill and all people will respect. A Syrian man anyone [in IS] can kill. But strangers [foreigners], only John."