Police have released CCTV footage that shows Ethan Mountain in the moments before and after he stabbed shop worker Joan Hoggett to death.
Mountain, 19, left his 62-year-old victim with 29 knife wounds in an attack at the One Stop Shop in Fulwell, Sunderland, last September.
READ MORE: CPS explain why Ethan Mountain was found not guilty of murder
The 19-year-old, who was carrying a bag of knives and wearing a horror mask when he carried out the killing, had admitted manslaughter but had denied murder on the grounds of diminished responsibility.
Listen to 999 call friend of Ethan Mountain makes to police after he stabbed Joan Hoggett to death
Mountain was being tried by a jury at Newcastle Crown Court, where prosecutors claimed the killing, which may have been part of a botched attempted robbery, was murder.
But today Mr Justice Butcher order the jury to deliver a not guilty verdict in respect of the murder charge.
Mountain now faces sentence for manslaughter, which will take place on Friday, March 22.
Earlier in the trial, the jury heard the sequence of events which led up to the killing - and Mountain's movements afterwards.
TIMETABLE TO KILLING
September 5, 2018
12:30pm Ethan Mountain meets a friend. They walk to Morrisons, then Martinos to play pool and then on to PureGym, in Newcastle Road.
5.30pm Mountain is seen on the gym's CCTV.
7.20pm He leaves the gym.
10pm CCTV from Heaton Gardens, South Shields, shows Mountain wearing a hooded top and carrying a large bag. He walks to East Boldon Metro station where he boards a train.
10.26pm Mountain gets off the train at Seaburn.
10.33pm Mountain enters the One Stop shop with a mask over his face and then produces a knife and repeatedly stabs shop worker Joan Hoggett.
10.34pm Mountain leaves the shop, crossing Sea Road and heads down Mere Knolls Road towards Roker Park.
September 6, 2018
2am Mountain calls at his friend's house asking to use his phone. He says he has stabbed someone. The pair go to a nearby park where Mountain asks his friend to tell the police and hand him in.
2.30am A 999 call is made to emergency services
2.40am Police go to an area near Whitburn Cricket Club and arrest Mountain