The father of a teenager stabbed to death walking home from a West Ham match says his son has been “failed by everyone” who had failed to come forward with information.
Law student Sami Sidhom, 18, was in Forest Gate, east London, on 16 April 2018 when he was attacked in a possible case of mistaken identity.
Nine people have been arrested but no-one has been charged over his death.
A £20,000 reward has been put forward to help find the killers.
Almost 18 months after Mr Sidhom’s death, his father Samer said: “We, his family, relive his murder every day knowing that a beloved son and an aspiring lawyer has been failed by everyone.
“My son’s killers are still walking the streets free of conviction or charge. I need you to provide the evidence to convict them.”
Addressing those who may know his killer, he said: “You know who you are and you have a choice. A choice to be someone that hides in the dark, or a brave person who sets the record straight.
“If you know the killers you already know they killed a perfectly innocent person for no reason whatsoever.”
Describing his son as a “kind young man who always tried to help his family, friends and colleagues”, Mr Sidhom said the student had done “everything right” and “fought hard to win his place in society” before “some cowards in the dark stabbed him in the back”.
A £20,000 reward is being offered for information that leads to the arrest and conviction of those responsible.
The nine boys and men arrested so far are aged between 15 and 35. Eight have been released while inquiries continue, while one, aged 17, has been told he faces no further action.
Det Ch Insp Mark Wrigley, from the Metropolitan Police, said: “Sami was almost home when he was attacked. I know that there were witnesses to what happened.
“People at the scene know who took Sami’s life and why. I urge you to come forward and tell the truth about what you know.”