Key Facts

• The boy was held at Feltham Young Offenders' Institute, which houses children aged 15 to 18.
• He was taken to hospital after the London Ambulance Service was called to the prison for an "unwell child."
• The ambulance crew included paramedics, an advanced paramedic, and an incident response officer.
• The boy died in hospital on Monday, April 20.
• The Youth Custody Service expressed sadness and sent condolences to the family and friends.
• The Prisons and Probation Ombudsman will investigate the circumstances of the death.
• The Metropolitan Police were contacted but no further details were given.
• Feltham Young Offenders' Institute holds young people who are on remand or convicted.