A trusted prison source has told Newshub that notorious killer Stephen Williams stabbed a fellow-inmate at Auckland Prison in Paremoremo on Sunday.
St John ambulance confirmed to Newshub a 30-year-old inmate was stabbed just before 3pm Sunday afternoon.
Williams is serving a life sentence for bashing his six-year-old step-daughter Coral Burrows to death in a P-fuelled rage in Featherston in 2003.
The source says Williams stabbed another convicted killer, Nikki Roper, with a piece of glass and a broom handle.
Roper is serving a life sentence for the murder of his ex-girlfriend Alexsis Maria Tovizi in Christchurch in 2010.
Williams has already been convicted for a previous stabbing in jail, while Roper has already been the victim of a serious attack while inside.
Auckland District Health Board says Roper's condition is stable.