A masked teenager who stabbed a shop assistant to death as she worked a shift at her store has been detained indefinitely.
Ethan Mountain, who was wearing a horror mask and had his hood up, launched a "50 second" attack on Joan Hoggett and left her with 29 knife injuries.
The attack, which happened shortly before closing time on September 5 last year, led to "catastrophic" blood loss, which sent the 62-year-old grandmother into cardiac arrest and resulted in her death.
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Mountain left a blue Nike holdall at the scene, which contained a sheathed ibben custom knife, a sheathed samurai sword, two sheathed machetes, a hunting knife, a hinged knife, clothing, and a document with his name on.
Newcastle Crown Court heard the grandmother’s death devastated her family, who struggle with the “terrifying circumstances” of her killing.
Her daughter Michelle Young said in a victim statement, which was read in court, that Mrs Hoggett was a "rock" to her whole family: “The whole situation seemed like a nightmare we would wake up from.
“Hearing the circumstances of my mam’s death doesn’t seem real.
“I just want life to be normal.”
Mrs Hoggett’s granddaughter Sarah Brown, who got married just a month before the killing, said in her statement: “Ethan Mountain has taken the sharpest tool from his bag and tore my whole family into a million pieces.
“He has caused so much heartache.
“The sadness and anger cannot be put into words."
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She added: “Ethan Mountain has left our whole family broken.
“Knowing she was dying on the shop floor, with no hand to hold, no-one to tell her she was loved, he took that away.
“Seeing that mask at court, on what would have been her birthday, and knowing it was the last thing she saw, we will never, ever get over.”
Mrs Brown said a song played at her wedding was also played at Mrs Hoggett’s funeral and her beloved grandmother was dressed in the special outfit she wore for the wedding ceremony at her funeral.
Mountain, 19, of Heaton Gardens, South Shields, who is currently detained in Rampton top security hospital, admitted manslaughter on the grounds of diminished responsibility.
The teen had originally been accused of murder but both prosecution and defence teams have accepted he was suffering an abnormality of mind at the time of the killing, which impaired his responsibility for it.
It was accepted on both sides Mountain is a paranoid schizophrenic and "very ill".
Mr Justice Butcher sentenced Mountain to a hospital order without limit of time.
The judge told him: "Your killing of her was a truly terrible event.
"She was simply doing her job, in the One Stop Shop in Road, Fulwell, on the evening of September 5 last year, when you entered the shop, masked, armed with a knife and carrying many more weapons, and launched, without warning, an entirely unprovoked assault on this defenceless lady, who you did not know."
During the case, the court was shown shocking CCTV footage from the shop, which captured the killing on camera.
The judge said: "It is impossible to watch the CCTV footage of the incident without a feeling of deep pity for Joan Hoggett, who had done nothing whatever to bring about this savage attack."
Mountain, who was the judge said is "capable of unpredictable and fatal violence", was given an indefinite hospital order under the Mental Health Act 1983.
The judge told him: "I consider that it is clear that you pose a significant risk of causing serious harm to members of the public by committing other offences."
If Mountain were ever to be released, this would have to be approved by the Home Secretary, under the advice of his doctors.
The judge said the hospital order was necessary "to protect the public from serious harm".
The court heard Mountain had been diagnosed with ADHD when he was just 12 and was detained in a psychiatric hospital between June and August 2017, where he made chilling revelations about his thoughts.
Mountain had told staff: "Everyone thinks that I am a good person, that's because of the ability to charm people and they trust me.
"You may think that's scary, someone having the thoughts I am having, to trick someone into thinking I'm a nice person when inside I want to seriously hurt them."
Mountain, who said he started taking cannabis at age 15 but cut back because he experienced "profound hallucinations" claimed to have harmed animals in the past and told medics: "Someone will get killed and then I will get arrested."
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The court heard Mountain was on a "low dose" of anti-psychotic medication when he was released from the psychiatric hospital in August 2017, a day before his 18th birthday, and started drinking vodka, heavily.
Mountain claimed he had stopped taking his prescribed medication "about a week before" he attacked Mrs Hoggett and was due to see a psychiatrist the following month.
During interview after the attack, Mountain told a psychiatrist he had been hearing voices and had had an argument with his mother just before the killing.
He added: "She was concerned I was drinking too much, I was concerned that the doctors would throw me back in hospital.
"The voices were saying I would be crazy and I would be sectioned."
Mountain said he had limited recollection of the actual attack on Mrs Hoggett.
He told a psychiatrist: "I can't remember physically doing it, I just remember walking to the shop, thinking people were talking about me and then I was coming out of the shop, covered in blood.
"I knew I had done something wrong, I went to the park and began self-harming."
CCTV footage that captured Mountain leaving his home in South Shields, walk to East Boldon Metro station and board a Metro train to Seaburn, carrying the rucksack.
After leaving the Metro at Seaburn station, Mountain walked to the shop and appeared to pause for around a minute, and put on the mask, before he entered the store.
The video recording from inside the shop showed Mountain, wearing a hood and mask, approach Mrs Hoggett as she worked in one of the aisles.
The killer then launched the attack, appeared to pause, and then continue the violence before leaving, after less than a minute.