An inmate has died in Otago Corrections Facility overnight - the second inmate to die at the prison within two months.
Prison director Jack Harrison said staff found the inmate in an unresponsive state this morning.
Mr Harrison said medical care was provided to the inmate, but efforts to resuscitate him failed and he died at the scene.
Corrections Minister Judith Collins told Checkpoint with John Campbell it was not known if the death was a suicide but there were between three and 12 suicides in prisons every year.
"It does happen. It's not acceptable. But in the general population, John, I think you've also got to look at the fact that we have almost 600 people a year out of the population who kill themselves. It's a terrible situation for everybody."
The death has been referred to the coroner, with the Prison Inspectorate and police investigating the death.
Another inmate died at the prison in November last year.