A man who claims to be the overall military commander of the Islamic State spoke with Tom Elliott via Skype this afternoon.In what listeners described as a "chilling" and "frightening" interview, Omar Shishani told 3AW Drive he would stop at nothing."We will push them all the way to Tehran. When we are finished ... we will come to Iran," he said.He claimed that Khaled Sharrouf, who is the man responsible for a horrific picture of a young boy holding the severed head of a Syrian soldier, was a good man.Sharrouf left Sydney last year to fight for the Islamic State in Syria.But speaking on 3AW Drive, the man claiming to be the Islamic State military leader defended the former Sydney resident's actions."He's a very loveable, good kid," he said."He's a faithful man."Meanwhile, the international director of the Global Terrorism Research Centre, Professor Greg Barton, said the interview was consistent with the research his centre had done into the militantgroup.updateMilitant on 3AW may be bogusRESPECTED academics in two countries have cast serious doubt onclaims by Fairfax Radio’s 3AW that a senior Islamic State militarycommander was the man it interviewed during a broadcast that shockedMelbourne listeners.Host Tom Elliott — who on Monday’s Drive program intervieweda man he claimed to be Omar al-Shishani — yesterday told listeners hestood by the broadcast, in which it was claimed the IS could come toAustralia.But he softened his stance about the man beingShishani, an ethnic Chechen-born Tarkhan Batira­shvili in Georgia,saying he believed now the interviewee had been “an Islamic militant”.The interview — conducted entirely in English — was quoted by several media organisations, including The Daily Mailand Seven News, because of the man’s praise for Khaled Sharrouf, an ISfighter who sparked international outrage after uploading a photographof his Sydney-born son holding the severed head of a soldier.Those who have studied the group said they would be shocked if asenior IS commander communicated with the West via Skype, given thegroup’s security fears.US academic Aaron Zelin, widely respectedfor his work on IS and other jihadist organisations for The WashingtonInstitute for Near East Policy and on his Jihadology website, said hewas not convinced the man was Batirashvili.“My initial reaction would be scepticism that it’s actually him,” Mr Zelin told The Australian on reviewing the interview. He was not aware Batirashvili spoke English.Greg Barton, of Monash University’s Global Terrorism Research Centre, said the man’s voice sounded like a caricature.“It’s highly unlikely that the voice in the interview is Omar al-Shishani,” Professor Barton said.“Althoughthe voice from the interview sounds like a caricature — almost likesomething Sacha Baron Cohen might make up — the actual content ringstrue.”He said the interviewee was more likely to have been an IS sympathiser or delegate.Family and friends have told TheWall Street Journal Batirashvili, 28, was raisedin relative poverty as a shepherd’s son before a brief stint in theGeorgian military. He was discharged after contracting tuberculosis in2010, jailed for harbouring weapons and then joined the jihad in Syriain 2012.Elliott told listeners yesterday he was aware of doubts that Batirashvili could speak English so well.“Priorto putting him on air, we did everything we could to establish hisidentity as genuine. We stand by our belief that the man ... was anIslamic militant fighting for the violent overthrow of the Iraqigovernment and the establishment of a fundamentalist caliphate. But youjust never know these days, do you?”