A prison officer is being questioned after being arrested at Limerick prison in possession of a number of mobile phones and drugs.
The man, who is in his 50s, was arrested at 8.30pm last night.
He was carrying up to 40 mobile phones, phone chargers and a quantity of cannabis and cocaine.
It is understood the arrest followed a lengthy garda operation stretching back several months.
The Prison Service has confirmed that an officer was arrested.
The Minister for Justice has made it an offence for anyone except the Governor to use a mobile phone in prisons.
Prison officers are only allowed to use mobile phones with the permission of the Governor.
The man is being questioned at Roxboro Garda Station and can be held for up to seven days.