The boss of Christchurch Men's Prison has been sacked.
John Roper was put on special leave last year while an investigation was carried out into covert surveillance of inmates.
Corrections regional commissioner Ben Clark says the review shows substandard practice at the prison and Mr Roper will not be returning to his job.
"The National Commissioner's decision followed the review into specific security matters at Christchurch Men's Prison and a subsequent employment investigation," Mr Clark said.
"The security review identified a number of substandard management and security practices at the prison, including failing to action a number of intelligence reports and telephone monitoring disclosures, use of cellphones and the use of covert audio devices."
Mr Clark said a higher standard of conduct is expected of employees.
"If any staff don't meet the standards required... we take appropriate action."
Two senior managers remain under employment investigation.
The police are running their own investigation after they were handed information about the review.
A summary of the security review commissioned by Mr Clark said there were breaches of the Corrections Act, Corrections Regulations, the Custodial Practice Manual and the Prison Operations Manual.
"There were identified weaknesses in the management of prisoners and the use of unauthorised items, including cellphones," the summary reads.
"The report further identified the actions of staff and favourable treatment being given to particular individuals."
It said there was unauthorised use of covert listening devices and cameras to intercept private communication.
The report was provided in August 2017, showing the employment review had taken more than a year.
Jo Harrez will take over as acting Prison Director for Christchurch men's prison at the end of the month, replacing Dave Pattinson, who returns to his role as prison director of Northland Region Corrections Facility.