There were also 70 assaults by prisoners on staff.
There were 320 assaults in Irish prisons last year.
250 involved prisoners attacking other inmates - with 64 in Cork jail, 44 in Castlerea in Roscommon, and 29 in Midlands Prison in Portlaoise.
Almost four out of every five involved prisoner-on-prisoner attacks.
Eoghan Murphy reports:
There were also 70 assaults by prisoners on staff.
Jim Mitchell, from the Prison Officers Association, says several staff have suffered serious injuries over the years
.

Spain To Launch €60 Unlimited Travel Pass As Irish Campaigner Calls For Better Service Frequency
Fines And Jail Terms Proposed For Sellers As Crackdown On Disposable Vapes Begins
Lower Childcare Fees Promised - But Providers Say They Are Being Ignored
Man Accused Of Assaulting 10-Year-Old In Saggart Tells Gardaí Child Said "She Was 18"
Up to 100 Maynooth Students Face School Travel Chaos After Bus Service Pulled
Children Eating At Desks And Walking On Public Roads As Curragh Community College "Bursting At Seams"
Jim Gavin Was Asked About Tenant Dispute Twice Before Being Selected As Fianna Fáil Presidential Candidate
Three Motorists Fined During Naas School Run As Children Were Not Wearing Seatbelts