Valdo Calocane: 'The errors were not technical, they were basic', victim's father says
Calocane - who has paranoid schizophrenia - fatally stabbed 19-year-old students Barnaby Webber and Grace O'Malley-Kumar before killing 65-year-old caretaker Ian Coates. Sky speaks with Grace O' Malley-Kumar's parents.
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A new report says that doctors had warned that the Nottingham attacker Valdo Calocane could have killed someone, three years before he went on a rampage in June 2023.