The Corrections Department is moving all of the inmates from Christchurch men's and women's prisons as a result of the earthquake. The transfers have already started.
The department says the move will eliminate any risk of putting more pressure on the stretched emergency services in Canterbury.
Principal operations adviser Lance Alexander says the prisons have been operating safely, but have increased the amount of time that inmates are locked in their cells.
Special flights began transferring the women to prisons in Wellington and Auckland 48 hours ago.
Some men have been taken to Otago by road.
Mr Alexander says they will be returned when emergency services are no longer under so much pressure.