Pledging to keep working to prevent sexual abuse by priests, the president of the United States Conference of Catholic Bishops expressed regret to children victimized in the past.

"We continue to apologize to the victims and to their parents and their loved ones for this failure in our pastoral responsibilities," Bishop Wilton Gregory said in a written statement Tuesday.

The remarks were a response to troubles in the Roman Catholic Archdiocese of Boston, where Cardinal Bernard Law has admitted he knew in 1984 that a priest had molested children, yet approved the priest's transfer to another parish and stayed publicly silent about the abuse.

More than 130 people have come forward claiming the former Rev. John Geoghan fondled or raped them between 1962 and 1995, and Geoghan has been convicted in one criminal case. Law has apologized and has given Massachusetts prosecutors the names of more than 80 active and former priests accused of sexual abuse.

The bishop in Manchester, N.H., followed suit this month, giving prosecutors the names of clergy suspected of molestation. Another bishop, in Portland, Maine, said Tuesday that they plan to do the same for clergy in the Maine diocese.

Gregory acknowledged that sexual abuse by priests, which first gained national attention in the mid-1980s, has done "immeasurable" damage to the church. He outlined steps taken by the U.S. bishops to address the problem nationwide, such as improving seminary screening and requiring a certificate of good standing for priests moving among dioceses.

"While we have made some tragic mistakes, we have attempted to be as honest and open about these cases as we can, especially in following the law on these matters and cooperating with civil authorities," he said. "We remain committed to seeing these initiatives implemented fully, because the church must be a place of refuge and security, not a place of denial and distress."

Gregory, who leads the Diocese of Belleville, Ill., said only a small percentage of the nation's more than 40,000 priests were guilty of molestation. He asked U.S. Catholics to work together to prevent abuse.