The 15-year-old, who was not identified, will serve at least five years in jail for inciting terrorism and will not be released until he is considered not to be dangerous. He may be released after five years under the terms of the ruling.
Sentencing the boy, who had pleaded guilty to one count of inciting terrorism, Manchester Crown Court Justice Saunders said: “Thanks to the intervention of the police in this country and in Australia, that attack and the deaths which were intended to follow never happened.
“Had the authorities not intervened, (the defendant) would have continued to play his part hoping and intending that the outcome would be the deaths of a number of people. In March 2015, he would have been pleased if that had happened. He would have welcomed the notoriety that he would have achieved.
“The revelation in this case that someone of only 14 could have become so radicalised that he was prepared to carry out this role intending and wishing that people should die is chilling.”
The plot intended to murder a number of police officers at the Anzac Day parade in Melbourne, held on April 25 each year to commemorate the Australian and New Zealand Army Corps’ in the World War One battle of Gallipoli.
The teenager, from Blackburn in north-west England, hugged his parents and family members after the sentence was passed down before he was taken away from the courtroom.
The court heard that the defendant was radicalised by an online jihadi community, accessed via his first smartphone, which prosecutors said had filled a void caused by problems at school and at home, as well as a degenerative eye condition.
The court was also told that a well-known Islamic State recruiter -- Abu Khaled al-Cambodi -- had instigated contact between the boy and alleged Australian jihadist Sevdet Besim, 18.
They exchanged over 3,000 encrypted messages, including one in which the British teen suggested Besim get his “first taste of beheading” by attacking “a proper lonely person”.
They also made references to making a martyrdom video, prosecutor Paul Greaney said.
The court heard that in an exchange on March 19, the teenager presented Besim with three options -- a gun attack on the police, a car attack on the police or a knife attack on the police.
“Besim expressed a preference for a combination of a car and knife attack and (the defendant) advised him to buy a machete and sharpen it, run over a police officer and then decapitate him,” Greaney said.
The teenager had been arrested on March 25 after concerns were raised by his school about his extreme behaviour, where classmates had nicknamed him “the terrorist”.
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