Security experts believe the black-robed killer ranting on the video has a distinct English accent, rather than another British person dubbing over the footage.The jihadist wears a black mask, concealing all but his eyes, making it difficult to be sure the voice belonged to him. But audio experts have claimed they are ‘99 per cent’ certain the words were spoken by the man seen on camera.Intelligence sources are understood to have identified the fanatic whose voice is heard on videos of the murders of Mr Haines, James Foley and Steven Sotloff, and are trying to track him down in Syria with state-of-the-art military technology.Jihadi John is thought to be one of 500 British Muslims fighting with IS to impose a caliphate in Syria and Iraq.Because of the devastating impact of air strikes on IS positions in northern Iraq, jihadist leaders are increasingly suspicious of Western fighters, amid fears they could be spies pinpointing enemy locations. But Jihadi John’s role in the latest murder suggests he remains a crucial member of the terror network and its propaganda war.Hostages freed earlier this year said the killer was one of three UK-born militants who held captives in Raqqa, Syria – who they nicknamed John, Paul and Ringo after members of The Beatles.Jihadi John is said to be the most intelligent of the trio. He has taken responsibility for communicating with the outside world via negotiations with the prisoners’ families and beheading videos.He also seems to have been in charge of security, reportedly ordering captives to be moved at least ten times to foil attempts to rescue them.Paul and Ringo are thought to have been more junior, but together with Jihadi John they carried out the most sadistic beatings.There were also French-speaking extremists among the guards, including at least one Belgian. But the British jihadists were the most feared because of their gruesome ‘taste for the macabre’, according to a freed French hostage.The violence included beatings, use of Taser guns, and waterboarding – a form of torture where water is poured over a cloth blocking the nose and mouth.They forced some of the Western prisoners to take part in mock killings – US journalist Mr Foley was forced to stand in a crucifix pose. The captives were also mostly kept underground in the dark, often shackled to one another.The first beheading video sent shockwaves across Britain as the killer spoke with a distinctive London twang and English appears to be his first language.Linguistic experts believe the way he pronounced certain words, such as Iraqi place names, suggest he has a foreign language background – indicating his parents or grandparents may have come from the Middle East. He appears to have a skin tone consistent with African, Middle Eastern or South Asian descent.Academics claim Jihadi John has a multicultural East London accent, a kind of ‘new cockney’. The voice patterns will have been studied in painstaking detail by security chiefs desperate to glean his identity and match it with snippets of conversation picked up in Syria.(dailymail.co.uk)Bakudaily.Az