A first time offender at Manawatu Prison has died in hospital -- two weeks after he was attacked in his sleep

Bradley King was on remand awaiting sentencing for minor burglary charges when his cellmate allegedly beat him so badly he was put into a coma.

King's sister described the 36-year-old as a gentle giant who was trying to keep his head down and wanted to make amends for his actions.

Police upgraded the case to a homicide investigation after King died yesterday.

A 29-year-old man was previously charged in relation to the incident and more charges may soon follow.