Eleven members of the same family were arrested last night as part of a major investigation into what gardai fear is the worst paedophile ring in the history of the State.
Six women and five men, ranging in age from their 20s to their 70s, were being questioned following raids in three counties across Munster.
It is understood that those arrested are from three generations of an extended family. All of them are Irish nationals.
The Herald has learned that last night's arrests centre on the sexual abuse of three children.
However, it is understood that at least a dozen children, who range from babies up to the age of 12, have been subjected to rape and sexual abuse.
More raids and arrests are expected in the coming months.
The family members involved are suspected of letting strangers rape and sexually abuse the children in exchange for cash.
A source told the Herald last night that gardai are most likely dealing with the worst paedophile ring in the history of the State.
Gardai said details emerging about the suspected sex abuse and exploitation of the victims were "horrific".
Sources described the investigation as "very sensitive".
They said the suspected abusers appeared to have been operating as part of an organised ring and seemed to be known to each other.
The arrests took place yesterday following raids on homes in Limerick, Tipperary and Kerry.
Specially trained gardai attached to the Limerick Divisional Protective Services Unit swooped on a number of properties and arrested the 11 suspects.
They were being held last night at garda stations in Limerick, Cork and Clare under Section 4 of the Criminal Justice Act. They can be held without charge for up to 24 hours, excluding rest periods.
Senior gardai said last night that the raids and arrests were the culmination of an investigation that had been under way for at least nine months.
The victims are understood to have been from west Limerick.
The massive garda operation included gardai from Newcastle West, Bruff, Henry Street, Mayorstone and Roxboro Road stations, all in Co Limerick, as well as the Limerick Divisional Protective Services Unit.
Gardai confirmed in a statement that they "arrested 11 adults (six females and five males ranging in ages from their 20s to 70s) as part of an investigation into alleged sexual exploitation of children who were resident in the New- castle West Garda District".
Childcare services have been alerted about the abuse and were informed last night about the arrests.
Tusla was notified about the suspected abuse more than a year ago, when some of the children were taken into care.
That information sparked the garda investigation that began in west Limerick and spread to other counties.
A reliable source confirmed that all of the 11 arrested people are part of the same extended family.
"All 11 were arrested in Limerick, Tipperary and Kerry and are detained at various garda stations in Limerick, Cork and Clare under the provisions of Section 4 of the Criminal Justice Act 1984," a garda statement went on to add.
Any child impacted by this story can contact Childline - available 24 hours a day by phone on 1800 66 66 66 and between 10am and 4am by text to 50101, or at webchat on Childline.ie