Sexual abuse at a children's home in County Down was equal to, if not worse, than abuse at Kincora Boys Home, an inquiry has been told.
The Historical Institutional Abuse (HIA) Inquiry is examining allegations of abuse at Rubane House, Kircubbin.
The inquiry estimates that 200 of Rubane's 1,050 former residents have made allegations of serious sexual or physical abuse.
A total of 13 Northern Ireland institutions are being investigated.
The Kircubbin home was run by the De La Salle religious order, which has already accepted some children were abused.
A lawyer acting for the inquiry said more than 200 children had claimed they were abused at Rubane House, which was open from 1950 to 1985.
A total of 55 former residents have come forward to the inquiry to allege that they were physically or sexually abused.
Their public testimony will begin next week.
Other documentation, including police reports, suggest that a further 150 boys also made allegations of abuse in the past, but have not contacted the inquiry.
The sex abuse allegations ranged from watching children in the shower to rape, while physical abuse ranged from corporal punishment to serious assault.
The inquiry has heard that the paedophile priest, Fr Brendan Smyth, was among the offenders.
Some children also alleged that they were sexually abused by older boys in the home.
The lawyer added that in 1997, a senior police officer, Det Ch Supt Eric Anderson described the sexual abuse of children at Rubane House as "rampant" and likened the scale of the abuse at Rubane House to that of Kincora Boys Home in east Belfast.
Kincora Boys Home was the subject of a high-profile child abuse scandal in the 1980s.
Three senior care staff at Kincora were jailed in 1981 for abusing 11 boys in their care.
In 1997, Mr Anderson wrote to the director of public prosecutions about the Rubane House allegations: "I consider the complaints made to show it to be on a par with, if not worse than, the abuse at the Kincora children's home.
"Sexual abuse by a considerable number of the De La Salle brothers on the children, and consequently between children was rampant."
The HIA inquiry was set up in 2013 to investigate child abuse in residential institutions in Northern Ireland over a 73-year period, up to 1995.
The Rubane House allegations form the third module of its public hearings.
It had previously been examining what happened to children sent from Northern Ireland to institutions in Australia.