The boy told police he had planned the robbery a couple of days earlier. He was "envious of other people who had material things he wanted." He admitted trying to separate the money after the robbery, cleaning himself up and going back to the scene to see how many police officers were in attendance.
In mitigation, his defence solicitor said that the facts if the case are "as startling as the are tragic." His family, she said, were "instrumental in bringing this young man to justice."
The boy told police upon questioning that he was sorry. His lawyer told the court he had an "impeccable character" and was "polite, courteous and obedient" and realised he has brought shame on his family.
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Greater Manchester Police said "inquiries are ongoing to fully understand the circumstances of the incident."