Ethan Mountain, who was wearing a horror mask and had his hood up, launched a "50 second" attack on Joan Hoggett in the One Stop Shop at Fulwell, Sunderland, and left her with 29 knife injuries which caused damage to her heart, lung, arteries and intestine.
WATCH: Family of Joan Hoggett make plea over knife crime as they urge those with mental health issues to seek supportThe attack, which happened shortly before closing time on September 5 last year, led to "catastrophic" blood loss, which sent the 62-year-old grandmother, from Grindon, into cardiac arrest and resulted in her death.
CCTV footage shows killer Ethan Mountain in moments before and after he stabbed Joan Hoggett to deathMountain left a blue Nike holdall at the scene, which contained a sheathed Hibben custom knife, a sheathed samurai sword, two sheathed machetes, a hunting knife, a hinged knife, clothing, and a document with his name on.The 19-year-old, of Heaton Gardens, South Shields, who is currently detained in Rampton top security hospital, admitted manslaughter on the grounds of diminished responsibility.
Listen to 999 call friend of Ethan Mountain makes to police after he stabbed Joan Hoggett to deathMr Smith said, whatever the outcome, Mountain will be detained for a "very, very long time indeed".Mr Justice Butcher agreed to adjourn the case until next Friday but added: "I am very reluctant to prolong the agony for the family in this most distressing case."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."