A 15-year-old boy has been sentenced to life with a minimum term of 16 years for murdering Sheffield schoolboy Harvey Willgoose in a lunch break knife attack.
Harvey, also 15, was stabbed twice in the chest by Mohammed Umar Khan outside their school cafeteria in February this year.
During sentencing at Sheffield Crown Court, judge Mrs Justice Ellenbogen told Mohammed Umar Khan his "senseless acts" were a "betrayal of your friendship" with Harvey.
She added the murder had a "devastating effect on Harvey's family" and their lives have been "blighted by your actions".
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Khan, who can now be named after the judge lifted reporting restrictions, took a 13cm hunting knife with him to All Saints Catholic High School.
CCTV showed Harvey arriving at the school, with earlier footage showing the attacker trying to provoke Harvey, who remained calm.
The attacker was also seen in footage holding a knife in the canteen before the stabbing.
The boy had previously admitted to manslaughter but denied murder. But in August, he was found guilty at Sheffield Crown Court by a majority verdict of 11 to one.
Defence lawyers claimed the boy had "lost control" after years of bullying and "an intense period of fear at school".
He told teachers after the stabbing "you know I can't control it" and "I'm not right in the head".
Following the murder, the parents of Harvey, Caroline and Mark Willgoose, told Sky News they wanted to see knife arches "in all secondary schools and colleges".
'Popular, energetic, full-loving'
Steve Davies, chief executive of St Clare Catholic Multi Academy Trust, which operates All Saints Catholic High School, described Harvey as "a popular, energetic and fun-loving pupil who is dearly missed every day by the whole school community".
He added: "Our thoughts are first and foremost with Harvey's family, loved ones and friends. We cannot begin to imagine the depth of their loss and our deepest sympathies go out to them today and every day.
"Since the conclusion of the trial, the school and trust have been able to engage fully with a number of ongoing investigations aimed at answering key questions about Harvey's tragic death. We will continue to work closely with these partners and cooperate fully with these investigations."
Katie Crook, associate vice principal of Penistone Grammar School, also called for schools to be "brave enough" to talk about knife crime.
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Mrs Cook said: "It's 100% a conversation, I think, that we need to be empowered and brave enough to have."
She added: "We're really lucky here that we don't have a knife crime problem - but we are on the forefront with safeguarding initiatives.
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'Our mental health has been destroyed'
Ahead of sentencing, Harvey's sister, Sophie Willgoose, described in her victim impact statement about the moment they were told about his murder.
"In that moment, our world was shattered forever," she said.
She described Harvey as a "cheeky character" with a "warmth that made everyone love him".
Ms Willgoose added: "The defendant didn't just end Harvey's life, he ended ours too. Our mental health has been destroyed."
Richard Thyne KC, prosecuting, said that while Khan had no previous convictions, he had previously taken an axe and a knife separately onto the school premises.
Khan and Harvey had "fronted up" to one another in confrontations at school, he added.
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