The abuse of more than 1,000 children for decades by hundreds of priests in Pennsylvania was systemically covered up by church officials, including the current archbishop of Washington, according to a grand jury report.
It says the real number of victims may be very much higher because records have been lost and some of those abused may be afraid to come forward.
The report claims more than 300 clergy were involved in the abuse, but only two have been charged, including one who has pleaded guilty.
In most cases the statute of limitations has expired, meaning charges cannot be brought. Some of the alleged abusers have since died, retired or have been dismissed from the priesthood.
The assaults are said to have ranged from groping to rape, with most, but not all of the victims, boys.
In one case a boy was made to pose naked as if being crucified and then was photographed by a group of priests who produced and shared child pornography on church grounds.
"We are sick over all the crimes that will go unpunished and uncompensated," the grand jury said.
At a news conference Pennsylvania Attorney General Josh Shapiro said church officials often dismissed or ignored allegations of abuse.
He said: "Church officials routinely and purposefully described the abuse as horseplay and wrestling and inappropriate conduct. It was none of those things. It was child sexual abuse, including rape."
He went on: "Priests were raping little boys and girls, and the men of God who were responsible for them not only did nothing. They hid it all."
The grand jury report accused Cardinal Donald Wuerl, who leads the Washington archdiocese, of helping to protect abusive priests when he was Pittsburgh's bishop between 1988 and 2006.
Cardinal Wuerl has rejected the allegations insisting he had tried to stop the abuse.
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"While I understand this report may be critical of some of my actions, I believe the report confirms that I acted with diligence, with concern for the victims and to prevent future acts of abuse," he said in a statement.
"I sincerely hope that a just assessment of my actions, past and present, and my continuing commitment to the protection of children will dispel any notions otherwise made by this report."