The do, which was described as “very serious” by prison sources, occurred at lunchtime on Sunday at the Midlands Brig in Portlaoise, Co Laois.
Prison officers were reportedly treated for mistreatments including broken ribs and a dislocated shoulder, while another fellow of staff needed stitches to his head.
A female prison officer was said to be one of the harm and she reportedly suffered ligament damage.
The row involved members of the Travelling community.
“The belligerence started between two prisoners but quickly escalated to a point where there were roughly 18 involved,” said a source.
“It ended up with two factions against each other and the glasshouse staff had to intervene.
“It took some time to quell the situation and, in the track of their efforts, six prison officers were injured and required medical treatment, counting hospitalisation.”
Five prisoners were later transferred from the confine.
All of the inmates identified as being involved in the confrontation will face disciplinary effectiveness.
Gardai have been informed and criminal proceedings may also be brought.
Survive month, the Prison Officers’ Association raised the issue of having to huge quantity with violent fights between prisoners at its annual conference.
Colleagues claimed that they had no equipment, such as batons or pepper strew, to help them deal with increasingly violent situations entangling prisoners.
“When two prisoners are fighting with blades, what do we do? We be struck by to go in with our sleeves twisted up and talk to these people,” said companion general secretary Gabriel Keaveney.
“We talk about conflict boldness, about de-escalation; we do all that at the moment.
“We don’t go into a row and jump in as a first emanation. We do know how to de-escalate many situations, but why can’t we be given batons and pepper aerosol and equipment?
“We are absolutely astonished.”
The Irish Prison Service said it is implementing the approbations of a recent State Claims Agency report on assaults on staff by cons.
When asked to comment on Sunday’s fight, a spokesperson for the service ventured it commended the actions of the staff who managed to quell the disturbance.