The inmate who died at Hawkes Bay Prison on Friday was Kolby Heta.
Police and the Department of Corrections are investigating the death of the 30-year-old.
It is understood Heta, from Gisborne, would be farewelled at a tangi tomorrow.
Detective Senior Sergeant Martin James said officers today hoped to get a "better understanding of the circumstances surrounding the death".
A post-mortem examination was conducted by a pathologist on Saturday but further investigations were needed.
Acting prison director Nephi Hall refused to be drawn on the specifics of Heta's death.
"Friday's incident at Hawkes Bay Prison is now a matter for the coroner and the Corrections Inspectorate," Hall told the Herald.
"Corrections can make no further comment at this stage."
He confirmed that the prison was locked down after Heta's death, which was "normal practice".
Corrections would not confirm any details about the deceased inmate.
But a prison source confirmed Heta's identity.
Another source said Heta was facing a charge of assaulting a female and was due to be sentenced on May 17.
When he was 23 Heta escaped custody at the Gisborne police station.
He was facing a charge of aggravated robbery at the time and had been remanded in custody ahead of a trial.
He was said to have Black Power links.