The UK's youngest murderers since James Bulger's killing have been handed longer sentences after judges agreed their original terms were too lenient.
The two boys, now 13 and who cannot be identified, were given life sentences with minimum terms of eight-and-a-half years for the murder of 19-year-old Shawn Seesahai in Wolverhampton on 13 November last year.
The solicitor general applied to increase those terms claiming they were "unduly lenient" because it was a "particularly serious type of case".
Judges at the Court of Appeal have now agreed to change their sentences to 10 years.
It means that - after time already served in detention - the pair will not be eligible for release until their early 20s.
The killers, who were both 12 at the time of the attack, were described during their sentencing in September as the country's "youngest knife murderers".
Mr Seesahai was stabbed through the heart and lungs and suffered a skull fracture during the attack on Stowlawn playing fields in East Park.
One of the wounds he suffered measured 23cm deep - almost passing through his body.
The two killers accused each other of wielding the machete but were found to be jointly responsible for the attack, which trial judge Mrs Justice Tipples called "horrific and shocking".
The boys are believed to be the youngest convicted of murder in the UK since James Bulger's 11-year-old killers in 1993.
During the initial sentencing, Mrs Justice Tipples said she had to consider the boys' "emotional maturity" and other factors based on their age and upbringing.
She said the "spur-of-the-moment attack" was not premeditated adding that one defendant was "extremely vulnerable" and had been "groomed and exploited" by others.
But the victim's mother Manashwary and father Suresh Seesahai said they were disappointed with the initial minimum sentences.
'Brutal and senseless' attack
On Thursday, responding to the new sentence, Mr Seesahai's family said: "Shawn's life was taken in a brutal and senseless act of violence.
"He was attacked with a weapon carried with clear intent, leaving us devastated and haunted by the thought of what he endured.
"While no sentence can ever bring Shawn back, we feel that today's decision better reflects the gravity of the actions that took him from us and acknowledges the immense loss we live with every day."
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Judge gave 'too much allowance'
At the Court of Appeal on Thursday, Paul Jarvis, representing the solicitor general, said Mrs Justice Tipples "made significantly too much allowance" for mitigating features.
Lord Justice William Davis, sitting with Mr Justice Bennathan and Judge Nicholas Dean KC, agreed: "We have, with some reluctance and sadness, come to the conclusion that the minimum terms imposed by Mrs Justice Tipples were unduly lenient."
Mr Seesahai, originally from Anguilla in the Caribbean, had been staying in Birmingham while recovering from cataract surgery and hoped to become an engineer in the UK.
Prosecutors said the unprovoked attack happened when he and a friend encountered a group of children in a Wolverhampton park. Mr Seesahai was punched, kicked and repeatedly knifed while on the ground.
The boys - known only as BGI and CMB in court - have been held in secure accommodation since the attack.
(c) Sky News 2024: UK's youngest knife murderers handed longer sentences over Shawn Seesahai murder