The Inspector of Prisons has been expressing concerns about bullying in Irish jails.
The Annual Report by Judge Michael Reilly, published today, says there is a culture where a minority of prison officers abuse their authority.
"There is a culture where a minority of officers abuse the authority vested in them to the detriment of prisoners," the report states.
"This can manifest itself in many ways and is insidious. It can involve such things as bullying, intimidation, name calling, failing to act on requests, making false promises, taking actions to ensure the discomfiture of prisoners and other actions designed to denigrate the prisoners under their control."
It also says prisoner by prisoner bullying is a major problem, and bullying by staff on staff "has been raised as a problem" - and says it is not satisfactory to rely on the fact that there is an effective complaints system in place.
The Inspector is conducting investigations into Wheatfield, Castlerea and Arbour Hill prisons and will submit reports to the Minister for Justice later this year.
A targeted investigation into certain aspects of Cork Prison is also to be conducted.