text: A middle-aged punk who fled Britain with her 10-year-old son to join Islamic State extremists  is believed to have been filmed leading women fighters in a hate-filled chanting session in Syria. Sally Jones, 45, who once played in a female punk band, ran away from her home in Chatham, Kent, to wage jihad with her toyboy husband in Raqqa, Syria, the terror group's de facto capital. A video has now emerged which appears to show the mother-of-two leading members of the al-Khanssaa Brigade - the all-women contingent set up by ISIS - in a series of chants expressing the fighters' commitment to jihad. Scroll down for video . In charge: Sally Jones, 45, a former punk rocker who fled the UK to join ISIS militants, is believed to have been filmed leading an all-women brigade of terrorists in a hate-filled chanting session in Syria . Leader: The mother-of-two, who slipped into Syria at the end of 2013 with her 10-year-old son, is seen punching her hand in the air and shouting Arabic chants, which are then echoed by her fellow militants . Experts say the slicky-edited video is the first 'real evidence' which shows Jones - who is believed to have set up home in Raqqa with her toyboy husband - is involved with the brigade at a 'high level' Experts say the slicky-edited video is the first 'real evidence' which shows Jones is involved with the brigade at a 'high level'. In the footage, a woman thought to be Jones is seen leading the female militia as they march single-file along a dusty road, waving their AK-47s in the air. The terrorists then gather in a group, shouting 'jihad' in chilling unison as they continue to thrust their weapons skywards. The three-minute footage also shows some of the fighters practising their shooting techniques, firing their guns in quick succession out of the camera's view. The footage then cuts to a woman, believed to be Jones, who is seen shouting furiously in Arabic, while punching her hand in the air. Surrounding her in a semi-circle,  her fellow terrorists echo her sickening cries. Although the woman is dressed in traditional Islamic dress, which covers her distinctive blonde hair, experts are now comparing the footage  to images of Jones to verify whether it is the same person. In the footage, a woman thought to be the former lead guitarist is seen leading the female militia as they march single-file along a dusty road, waving their AK-47s in the air . The three-minute footage also shows some of the fighters practising their shooting techniques, firing their guns in quick succession out of the camera's view . A security source told the Daily Mirror: 'Her public statements cause great concern and are being taken incredibly seriously. The threat she poses to our security should not be underestimated.' The Muslim convert, who was once an aspiring rock musician, is thought to have sneaked into Syria at the end of 2013 after an online romance with Junaid Hussain, 20. She fled the UK with her son Jojo, who she now calls Hamza, while her 18-year-old son was left behind. Since then, Jones has posted a series of chilling threats on social networking sites. She also posed for photos with an AK-47, while dressed in black with her face veiled. The mother-of-two, who lives on benefits while in the UK, was the lead guitarist in an all-girl rock band called Krunch during the early 1990s. The band played a series of gigs in the South East . Jones's family has previously said they are deeply shocked by the musician's conversion to radical Islam . The former lead guitarist - who spent a lifetime on state benefits while living in the UK - also ranted online about how she wanted to behead Christians with a ‘blunt knife’. Using the pseudonym Umm Hussain al-Britani, she also abused Jews and praised Osama bin Laden. Her family has previously said they are deeply shocked by her conversion to radical Islam. In the early 1990s she was the lead guitarist in an all-girl rock band called Krunch who played a series of gigs in the South East. She has previously posted a series of chilling threats on social networking sites and posed for photos with an AK-47, while dressed in black with her face veiled . A clip of one of her performances posted online shows her with a shock of blonde hair and wearing a leather mini-skirt. Meanwhile, Jones's husband Hussain is the leader of a computer hacking group known as Team Poison. He fled Britain while on police bail suspected of violent disorder in Birmingham. He was also jailed for six months in 2012 for stealing sensitive information from an aide of Tony Blair and blocking a government anti-terrorist hotline with prank calls. Hussain travelled to the warzone with Abdel-Majed Abdel Bary, 24, a former rapper dubbed the ‘hip hop jihadi’. Both men now fight for IS and are suspects in the killing of Mr Foley.
target: Guitarist Sally Jones, 45, ran away to Syria from Chatham, Kent, in 2013 .
  Mother-of-two set up home in Raqqa with toyboy husband Junaid Hussain .
  Footage shows her leading fighters in Arabic chants while waving AK-47s .
  Experts say video is first 'real evidence' she is involved with all-women al-Khanssaa Brigade at 'high level'