(CNN) -- The Archdiocese of Dublin and other Catholic Church authorities in Ireland covered up clerical child abuse until the mid-1990s, according to a government-commissioned report released Thursday.

The Dublin Archdiocese Commission of Investigation's 720-page report said that it has "no doubt that clerical child sexual abuse was covered up" from January 1975 to May 2004, the time covered by the report.

"The Dublin Archdiocese's pre-occupations in dealing with cases of child sexual abuse, at least until the mid 1990s, were the maintenance of secrecy, the avoidance of scandal, the protection of the reputation of the Church, and the preservation of its assets," the report said.

"The welfare of children, which should have been the first priority, was not even a factor to be considered in the early stages," it said.

"Instead the focus was on the avoidance of scandal and the preservation of the good name, status and assets of the institution and of what the institution regarded as its most important members -- the priests."

Archbishop Diarmuid Martin apologized Thursday in a news conference. "No words of apology can ever be sufficient," he said.

And Dermot Ahern, Ireland's justice minister, said he felt a "a growing sense of revulsion and anger" as he read the report.

"Bottom line is this: A collar will protect no villain," he said.

The commission was set up in March 2006 to look into allegations of child sexual abuse made against clergy in the Irish capital. Its report was completed in July.

Although the commission said it was not its place to "establish whether or not abuse occurred ... it is abundantly clear ... that child sexual abuse by clerics was widespread throughout the period."

One victim, Marie Collins, said those who covered up the abuse were just as guilty as the perpetrators of the crimes.

"How many people accused of abuse are still sitting in parishes today?" she asked in a Thursday news conference.

The commission examined the histories of 46 priests, who were picked as a sample from 102 who had had complaints or suspicions of child abuse raised against them. Complaints from more than 320 children were leveled against the 46, the report said.

But it said that the number of children abused likely exceeded that.

"One priest admitted to sexually abusing over 100 children, while another accepted that he had abused on a fortnightly basis during the currency of his ministry which lasted for over 25 years," the report said.

"The total number of documented complaints recorded against those two priests is only just over 70."

In its analysis of the 46 priests, the commission said that all four archbishops -- Archbishops John Charles McQuaid, Dermot Ryan, Kevin McNamara, and Desmond Connell -- who served during the time period covered by the report handled the child sexual abuse complaints "badly."

"Not one of them reported his knowledge of child sexual abuse to the Gardai (the Irish police force) throughout the 1960s, 1970s, or 1980s," the report said.

The commission did credit Connell, who took over the archdiocese in 1988, with giving Irish authorities in 1995 the names of 17 priests against whom complaints had been made -- although it called the number incomplete, saying that there was "knowledge within the Archdiocese of at least 28 priests against whom there had been complaints."

They said he was "slow to recognize the seriousness of the situation."

Connell also gave authorities permission to access the archdiocesan files in 2002.

Connell, a cardinal, apologized in a written statement. "I wish to express without reservation my bitter regret that failures on my part contributed to the suffering of victims in any form," he said.

"Although I am all too aware that such apologies and expressions of regret can never be adequate as a response to so much hurt and violation and, in any case, lose their value through repetition, I apologize again now from my heart and ask the forgiveness of those who have been so shamefully harmed."

The report named 11 priests who had pleaded guilty to or were convicted of sexual assaults on children. Of the other 35, it gave pseudonyms to 33 of them and redacted the names of two.

The report shot down the notion that church leadership was unaware of the problem. "The Archdiocese of Dublin and other Church authorities have repeatedly claimed to have been, prior to the late 1990s, 'on a learning curve' in relation to the matter," it said.

However, it said McNamara, Ryan and McQuaid had information on complaints against at least 17 priests when the Archdiocese took out insurance in 1987 to cover future compensation claims and lawsuits related to sexual abuse allegations.

"The taking out of insurance was an act proving knowledge of child sexual abuse as a potential major cost to the Archdiocese and is inconsistent with the view that Archdiocesan officials were still 'on a learning curve' at a much later date, or were lacking in an appreciation of the phenomenon of clerical child sex abuse," it said.

The report also said church officials perpetuated the problem by ignoring allegations and in some cases simply moved an alleged abuser on to another parish -- leaving him free to abuse another group of children.

Thursday's findings follow a report that came out in May, detailing allegations of child abuse in various institutions across Ireland from the 1940s to the present. Though both reports deal with child abuse, they are not related, having been written by two separate commissions investigating two different subjects.

The May report looked at child abuse in lay institutions, including reformatories, hospitals, orphanages, children's homes and industrial schools across the country. Some of those institutions were linked to religious orders, but none were strictly religious schools.

Speaking last month after the Irish High Court cleared the way for Thursday's report to be made public, Irish Justice Minister Dermot Ahern said he was pleased the information would not be kept private.

"I have always made it clear that I have been anxious to put the report into the public domain as quickly as possible, while at the same time not wishing to do anything which would prejudice the chances of any of the people involved in these evil deeds being brought to justice," Ahern said in a statement.

CNN's Atika Shubert contributed to this report.