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7 March 2016, 17:07
It was a row that started over a biscuit and name-calling, but quickly escalated into much more than just a scuffle between two teenage boys.
The pair had not been enemies before the fatal fight.
But on the afternoon of October 28 last year at Cults Academy in Aberdeen, an argument broke out between them and ended with 16-year-old Bailey Gwynne stabbed in the chest.
The blade pierced his heart and led to a "catastrophic'' loss of blood despite the efforts of paramedics to save him.
He was pronounced dead at Aberdeen Royal Infirmary and a 16-year-old boy was taken into custody.
Onlookers said Bailey and the boy threw punches at one another in a corridor after Bailey refused someone a biscuit.
It emerged during the trial that Bailey, a fifth-year pupil, reacted to a comment about his mother by punching the boy, who cannot be identified because of legal reasons.
The accused told police he pulled a knife from his pocket to scare Bailey and did not mean to stab him. A knife with a 8.5cm blade was later recovered from a waste bin at the school.
Computing teacher Alasdair Sharp disrupted the fight and led them towards an office, but Bailey started staggering and he turned around to see a trail of blood along the corridor.
An ambulance was called and Bailey was taken to Aberdeen Royal Infirmary but he did not survive the injury.
In the hours immediately following Bailey's death, Police Scotland described it as a "shocking and extraordinary'' incident for Aberdeen.
The school is in an affluent suburb of the city and has previously topped the league tables on the basis of its exam results.
Head teacher Anna Muirhead said the school community was "totally devastated'' and in shock as she led tributes to the dead pupil, describing Bailey as "gentle'' and "caring''.
Social media was flooded with messages from friends of the teenager, who all expressed their shock at what happened.
Nearby churches opened in the evening to offer support to the community. A candlelit vigil was arranged for the following evening as pupils, staff and locals tried to come to terms with the "terrible event''.
First Minister Nicola Sturgeon, speaking in the Scottish Parliament the day after the stabbing, also expressed her "shock and sadness''.
She stressed such incidents were "extremely rare in our schools'' and pledged the Scottish Government would make sure that any lessons which needed to be learnt would be learnt.
She made the comments during an exchange with Kezia Dugdale at Holyrood, in which the Scottish Labour leader described the fatal incident as "every parent's worst nightmare''.
It came as Bailey's family paid tribute to a "beloved boy'' who "never failed to make us smile''.
They said: "We don't know what we will do without our junior 'man about the house'.''
That evening, hundreds of people gathered to remember him at the informal vigil.
Messages left on boards around the church included "heal the hole in our hearts'' and "you will be missed so badly, Bailey''.
One message dedicated to the teenager who had talked of his wish to join the Royal Marines, read simply ''soldier on soldier.''
Meanwhile, hundreds of floral tributes continued to be left at the school gates, which were viewed by Bailey's family in a private visit in the coming days.
In a statement released through police afterwards, they said: "For all of you that were part of his life, however big or small, thank you for being there.''
As pupils returned to the school on the Monday for the first time since the incident the previous Wednesday, Ms Sturgeon, who was in the city for a meeting with police and council leaders, said the Scottish Government stood ready to provide any help needed in the weeks and months ahead.
"Bailey will never be forgotten but as the students return to Cults Academy today, I hope that they can begin to see a semblance of normality and begin the healing process,'' she said.
"The response to this tragedy - from everyone in Aberdeen - has been truly remarkable and I hope that the community spirit and support we have seen can offer a small amount of light in the city at this difficult time.''
Emotions were high during the five-day trial which saw a teenage witness break down as he gave details of the fight and the accused himself started crying when the jury heard how he was handcuffed by police who attended the school.
Describing events after the stabbing to police, the accused said he told Depute Head David Strang: "I know he's going to die, I'm going to prison.''