Two teenage brothers have been found guilty of killing schoolboy Damilola Taylor nearly six years ago.
The Preddie brothers were 12 and 13 at the time
Danny and Rickie Preddie, aged 18 and 19, of Peckham, London, were convicted at the Old Bailey of manslaughter.
Damilola, 10, bled to death after being cut with a broken bottle in south London. The inquiry into his death has led to three trials and cost £16m.
His parents said it was a great comfort justice had finally been done. "We pray his gentle soul can now rest in peace."
The Preddie brothers will be sentenced at a later date.
Nigerian-born Damilola was found bleeding from a leg wound in a stairwell on a housing estate in Peckham in November 2000.
It is thought he was attacked as he made his way home from an after-school club and was jabbed with a broken beer bottle in his thigh.
The long investigation included a much-criticised trial of four other youths in 2002 - all of whom were cleared.
Earlier this year the Preddie brothers and a third defendant, Hassan Jihad, 20, went on trial for murder after new forensic evidence, apparently missed during the first investigation, was found.
Mr Jihad was cleared of all charges, the Preddies were cleared of murder and assault but the jury failed to reach verdicts on the manslaughter charge.
Damilola's parents Gloria and Richard Taylor, who have sat through all three trials, watched calmly as jurors on Wednesday found the Preddies guilty of manslaughter.
But as the verdicts were read out, Rickie Preddie started shouting at the jury: "You are corrupt. You are nothing."
He was eventually taken out of court on the order of the judge.
The brothers, 12 and 13 at the time, were arrested a few days after Damilola was killed but were released without charge.
One was being monitored by the probation service and the other was on bail and detained at a children's home.
Damilola's parents have sat through three trials
They were re-arrested last year when the blood and fibres from Damilola were found on their clothing.
The jury heard they had convictions for robbery, some at knifepoint, and witnesses claimed the brothers had confessed to the killing.
A friend of Damilola told police he thought Danny Preddie may have come off worse in a fight with Damilola, who had broken his gold chain.
It is thought Damilola was surrounded by a gang of youths in Blakes Road, Peckham, and stabbed in his left thigh.
By the time he limped along the road and up two flights of a filthy stairwell, he was near death.
Commander Dave Johnston, of the Metropolitan Police, said the case had sent "shockwaves throughout London and beyond" and paid tribute to the courage and dignity of the Taylors.
He defended the estimated £16m cost of all three trials saying: "We believe that the money is well spent to bring justice in this very important case."
On the subject of the missed forensic evidence he added: "I am dismayed that the evidence was not found sooner and of course that will be a matter of ongoing investigation."
Lawyer Tony Connell, of the Crown Prosecution Service, also paid tribute to the Taylor family. He said: "They have borne the dreadful suffering since the death of this fine young man with immense strength and we have all been grateful for their support throughout this case."
Speaking outside court, Damilola's father Richard said: "Nobody can ever return our son to us, but it is a great comfort that justice has finally been done for Damilola."
Local MP Harriet Harman added: "The whole community will be relieved to know that justice has finally been done."
DAMILOLA TAYLOR'S FINAL JOURNEY
1: On 27 November 2000, Damilola Taylor finishes his day as normal at Oliver Goldsmith Primary School in Peckham, south London.
2: He heads to Peckham Library to attend a computer class. At about 1630 CCTV cameras capture him running and skipping as he leaves for home on the North Peckham Estate (since demolished and re-developed).
3: In Blakes Road minutes later he is cut with a broken bottle. He staggers 20 yards further, leaving a trail of blood, to a block of flats.
4: At around 1645 a local man finds Damilola collapses in a stairwell. He is taken to hospital where he dies from blood lost through a severed artery in his leg.