Intelligence agencies search IS video for Australians in death cult beheading squad A British medical student and a Frenchman are believed to appear in a video showing Islamic State jihadists beheading Syrian soldiers and displaying the severed head of an American aid worker. Vanessa Johnston reports. Jihadi John, Frenchman identified in IS video David Cameron and Barack Obama deplore barbaric acts Condolences sent to family of aid worker Peter Kassig AUSTRALIAN intelligence and security agencies are examining chilling images of up to a dozen terrorist fighters in the act of beheading victims to identify any involvement by Australians. The images have been posted by the Islamic State along with video of the beheading of US aid worker Peter Kassig. However, unlike previous images in which the barbaric acts have been carried out by a hooded man, the latest pictures of mass beheadings show the identity of the murderous culprits. Senior government sources confirmed the counter-terrorism agencies were carefully examining all the latest images. Members of the Islamic State jihadist group preparing the simultaneous beheadings of at least 15 men described as Syrian military personnel in the propaganda video. "Security agencies are aware of the footage and are examining it for any useful intelligence," a source said. It is believed they could not confirm yet whether any of the murderers were Australians known to have fled to the Middle East to become foreign fighters with the IS death cult. The images are among the most gruesome yet. In the highly choreographed sequence, jihadists march the prisoners by a wooden box of long military knives, each taking one as they pass, before forcing their victims, reportedly Iraqi pilots and officers, to kneel in a line and decapitating them. American aid worker Peter Kassig leaning against a truck at unknown location. The video also shows "Jihadi John" - the British citizen who became the Islamic State's chief executioner - leading the group of unmasked jihadists in the mass beheadings. The video puts into question claims Jihadi John was injured in a recent air strike. UK Prime Minister David Cameron said efforts to hold the murderer to account were continuing. "I want Jihadi John to face justice, you know, for the appalling things, the appalling acts, that have been carried out in Syria," he said. Mr Cameron also condemned Kassig's alleged death, saying he was "horrified by cold blooded murder" of the aid worker. Jihadi John has also been identified in the video. US President Barack Obama also denounced the terror group, stating that Kassig, who founded an aid group to help Syrians, "was taken from us in an act of pure evil by a terrorist group that the world rightly associates with inhumanity." The slain hostage's parents, Ed and Paula Kassig, said they were "heartbroken" by their son's killing, but "incredibly proud" of his humanitarian work. With Kassig's death, IS has killed five Westerners it was holding. American journalists James Foley and Steven Sotloff were beheaded, as were UK aid workers David Haines and Alan Henning. Meanwhile, former Sydney boxer turned terrorist Mohamed Elomar - who posted photographs of himself holding the heads of soldiers - has not contacted his family in months. Family friend Dr Jamal Rifi said it appeared Elomar had not been active on social media after having multiple accounts shut down by Facebook and Twitter. French prosecutors said a young Frenchman has been identified as one of the jihadists in the Islamic State video. The IS militant that the French government say is Frenchman Maxime Hauchard. Our cartoonist Warren has a crack at the aspiring jelly-belly jihadis. Originally published as Hunt for Aussies in death cult beheading squad