A court has heard how a 14 year old boy - thought to be Britain's youngest terrorist - plotted a massacre after becoming obsessed with propaganda by so-called Islamic State. The Blackburn teenager has admitted to his part in a plan to behead police officers at an Anzac Day parade in Australia. He spent hours talking to an online jihadist community and had previously threatened to kill one of his teachers. His mother wept in court, as new details of the plot were revealed at his sentencing.