Corrections says a steep increase in prison assaults is due to better reporting of incidents.
New data shows there were more than 2600 assaults in the last financial year.
It includes more than 1500 prisoner-on-prisoner assaults, and more than 1000 on staff.
Custodial Services Commissioner Leigh Marsh told Mike Hosking they've been working hard to improve how they deal with these incidents.
He says the encouragement of reporting assaults has seen an increase in the number of non-injury assaults being reported, which where the biggest number lies.
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