Classmates leave a T-shirt and school ties on railings near the murder scene
Family and friends of 16-year-old Jimmy Mizen have remembered him at a mass held at his school.
The mass at St Thomas Moore Catholic Comprehensive in Eltham, south-east London, was attended by Jimmy's family and more than 100 Year 11 pupils.
Jimmy, who was 16 on Friday, was attacked in a baker's shop in Lee, south-east London, on Saturday.
His mother earlier said his family are experiencing shock, horror and pain following her son's death.
Several of Jimmy's fellow pupils and friends also tied school ties on to railings today close to the Three Cooks Bakery where Jimmy was murdered on Saturday morning.
They also left two school blazers, birthday balloons and a shirt bearing the simple message "Jimmy Mizen, Legend" outside the bakery.
Police believe Jimmy had tried to avoid a fight minutes earlier
Jimmy, described as a "gentle giant", had set out to buy his first lottery ticket.
Police believe he had tried to avoid a fight minutes before being assaulted and suffering a fatal neck injury.
The bakery remained cordoned off on Monday and scores of floral tributes and messages of condolence were left nearby.
One message read: "Words cannot express my sorrow. I wish I could have done more at the time. God bless" while another said: "Rest in peace Jimmy boy, never forget you mate."
Det Ch Insp Cliff Lyons, leading the investigation, said Jimmy encountered his attacker after going into the bakery, which is less than 500 yards from the family home, with an older brother.
He said officers had gathered CCTV footage and "significant" forensic samples and also made a fresh appeal for other witnesses to come forward.
He said: "It was Jimmy's birthday on Friday and today would have been his last day at school - a time any parent will know marks the transition from teenager to adult.
"In keeping with this and his good nature, Jimmy showed great maturity and refused to react to the antagonistic actions of the suspect."
Police are still interviewing a "significant witness" - a man who was said to have seen a significant part of the attack on Jimmy.
The mass held at Jimmy's school was meant to be a celebratory leavers' Mass before starting revision for GCSE exams but the occasion became a tearful service of remembrance for Jimmy's family and friends.
Father Michael Scanlon, Dean of Greenwich, who helped lead the mass, called for action to make the streets safe so other youngsters did not meet his fate.
"We need our politicians and those in authority to react to situations like this, we need our streets to be safe again for everyone.
A group set up in Jimmy's memory on the Facebook website has already been joined by more than 1,800 users, many of whom did not know the schoolboy.
Jimmy is the 13th teenager to have been fatally attacked in London since the start of the year.