An inmate described as a "gentle giant" who was violently attacked in his cell at Manawatū Prison as he slept has died.
Bradley King, 36, died yesterday.
He had been fighting for his life after the brutal assault on February 11 but succumbed to catastrophic head injuries.
His family have been at his side and are devastated.
Twin sister Bridget King said he was a great friend but "most importantly" a great brother.
The family were not ready to speak further about King's death.
Police confirmed this morning that the investigation into the assault has now been scaled up and serious charges were likely.
"Police would like to extend our sympathies to his family and friends," Detective Senior Sergeant Craig Sheridan said.
"The inquiry into the incident has now been upgraded to a homicide investigation.
"A 29-year-old man had previously been charged with wounding with intent to cause grievous bodily harm in relation to the assault.
"He is next due to appear in the Dannevirke District Court on April 30, 2021.
"Investigators will now conduct further inquiries to determine what, if any, further charges will be filed."
Bridget King said her brother was a "beautiful gentle giant" and the "minor" offending that led to him being locked up was a "mistake he was so sorry for" and wanted desperately to make amends for.
"We're broken, we're hurt, we're so, so angry ... we just want to know what happened."
King was charged with a number of counts of burglary from commercial sites.
His family said it was the first time he had been in trouble, before the courts or in custody.
He had applied for bail but his sister said police opposed that and he was held on remand.
"He was in prison for 10 days and he was terrified, but he made friends and he kept his head down," Bridget King told the Herald today.
"He was attacked in his sleep, he didn't stand a chance."
A Corrections spokesperson confirmed both King and his alleged attacker had not been in custody before.
They arrived in prison on the same day.
"The alleged perpetrator has been segregated," the spokesperson said.
"Corrections is carrying out an operational review into the incident, and police are also investigating.
"We appreciate that this is a very distressing situation for them, and staff have visited the hospital to offer them our support.
"We have a zero-tolerance for violence policy, and any violence or assaults against other prisoners or staff is not tolerated in prisons. Any prisoner using such behaviour will be held to account for their actions, including facing criminal charges."
Bridget King said her twin brother sustained catastrophic brain and head injuries, multiple skull and facial fractures, brain bleeds, a punctured lung and broken ribs.
At the time she said: "He's in an induced coma ... We are living hour by hour with him ... we sit by his bedside, we talk to him ... we are with him."
She said the family had a lot of questions about what happened, why and the decision around who he was sharing a cell with.
"What we want people to know is that he didn't deserve this - he was on remand for three small commercial burglaries, he was going to plead guilty and he was so, so remorseful," she said.
"He comes from a huge, loving family and he is so loved.
"He's our gentle giant, he's never hurt anyone and he would help anyone who needed it ... he wouldn't hurt a fly.
"Yes, he did small burglaries but he had admitted that, he wanted to say sorry - and before a judge. They need to realise he's not a bad person, he's got a family and friends who love him so much and he had a lot of remorse.
"Yes, he made a mistake, he knew that and he wanted to make it right. "