A 23-year-old inmate has been charged with murder following the death of another inmate at Mt Eden Prison.
Andrew Chan Chui, aged 39, of Ōtāhuhu died at the facility on Friday.
In a statement, Detective Inspector Glenn Baldwin said a post-mortem and formal identification took place at the weekend.
"Today, investigation staff have charged another inmate, a 23-year-old man, with Mr Chan Chui's murder.
"He is expected to appear in the Auckland District Court on Thursday, appearing via audio visual link."
Baldwin said police were in ongoing communication with Chan Chui's family and making sure they were supported.