Bishops and other leaders of the Roman Catholic Church in Pennsylvania covered up child sexual abuse by more than 300 priests over a period of 70 years, persuading victims not to report the abuse and law enforcement not to investigate it, according to a searing report issued by a grand jury on Tuesday.

The report, which covered six of the state’s eight Catholic dioceses and found more than 1,000 identifiable victims, is the broadest examination yet by a government agency in the United States of child sexual abuse in the Catholic Church. The report said there are likely thousands more victims whose records were lost or who were too afraid to come forward.

It catalogs horrific instances of abuse: a priest who raped a young girl in the hospital after she had her tonsils out; a victim tied up and whipped with leather straps by a priest; and another priest who was allowed to stay in ministry after impregnating a young girl and arranging for her to have an abortion.

The sexual abuse scandal has shaken the Catholic Church for more than 15 years, ever since explosive allegations emerged out of Boston in 2002. But even after paying billions of dollars in settlements and adding new prevention programs, the church has been dogged by a scandal that is now reaching its highest ranks. The Pennsylvania report comes soon after the resignation of Cardinal Theodore E. McCarrick, the former archbishop of Washington, who is accused of sexually abusing young priests and seminarians, as well as minors.

“Despite some institutional reform, individual leaders of the church have largely escaped public accountability,” the grand jury wrote. “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. For decades.”

The grand jury said that while some accused priests were removed from ministry, the church officials who protected them remained in office or even got promotions. One bishop named in the report as vouching for an abusive priest was Cardinal Donald Wuerl, now the archbishop of Washington. “Until that changes, we think it is too early to close the book on the Catholic Church sex scandal,” the jury wrote.

The report is unlikely to lead to new criminal charges or civil lawsuits under the current law because the statute of limitations has expired. Only two of the cases in the report so far have led to criminal charges.

[Read about how Catholics are reacting to the shocking report here.]

In statements released on Tuesday, Pennsylvania’s Catholic bishops called for prayers for victims and for the church, promised greater openness and said that measures instituted in recent years were already making the church safer.

But several bishops, including Bishop David A. Zubik of Pittsburgh, rejected the idea the church had concealed abuse.

“There was no cover-up going on,” Bishop Zubik said in a news conference on Tuesday. “I think that it’s important to be able to state that. We have over the course of the last 30 years, for sure, been transparent about everything that has in fact been transpiring.”

Church officials followed a “playbook for concealing the truth,” the grand jury said, minimizing the abuse by using words like “inappropriate contact” instead of “rape”; assigning priests untrained in sexual abuse cases to investigate their colleagues; and not informing the community of the real reasons behind removing an accused priest.

“Tell his parishioners that he is on ‘sick leave,’ or suffering from ‘nervous exhaustion.’ Or say nothing at all,” the report said.

Attorney General Josh Shapiro, whose office initiated the investigation, said in a news conference, “They protected their institution at all costs. As the grand jury found, the church showed a complete disdain for victims.”

He said that the cover-up by senior church officials “stretched in some cases all the way up to the Vatican.”

No other state has seen more grand jury investigations of abuses in the church than Pennsylvania, where about one of every four residents is Catholic and the local attorneys general have been particularly responsive to victims. Previous grand juries examined the dioceses of Philadelphia and Altoona-Johnstown; the new report covers the rest of the state.

Mr. Shapiro was surrounded on Tuesday by about 20 abuse victims and their family members, who gasped and wept when he revealed that one priest had abused five sisters in the same family, including one girl beginning when she was 18 months old.

Some victims said in interviews that they were relieved to finally be heard and to have their perpetrators publicly named.

“I had gone to two bishops with allegations over five years, and they ignored and downplayed my allegations,” said the Rev. James Faluszczak, an Erie priest on extended leave who was abused as a child and who testified before the grand jury. “It’s that very management of secrets that has given cover to predators.”

For others, it was too little, too late. Frances Samber, whose brother Michael was abused by a priest in Pittsburgh and committed suicide in 2010, said, “It’s good that the public sees this, but where is the justice? What do you do about it? Why aren’t these people in prison?”

There has been no comprehensive measurement of the full scope of child sexual abuse in the Catholic Church in the United States, though somehave tried. American abuse survivors have pushed for years for the government to undertake a nationwide inquiry similar to the one conducted in Australia, where a royal commission spent four years examining the sexual abuse of children by a variety of religious and civic institutions, including the Catholic Church.

There have been 10 previous reports by grand juries and attorneys generalin the United States, according to the research and advocacy group BishopAccountability.org, but those examined single dioceses or counties.

The Pennsylvania grand jury report lands as the sex abuse scandal in the church has reached a new stage, with calls to discipline bishops who sexually abused younger priests and seminarians, or who have covered up for abusive colleagues.

Catholics are calling for independent investigations into why Cardinal McCarrick was advanced up the hierarchy despite warnings to his superiors in Rome and fellow bishops that he had molested seminarians and young priests. Cardinal McCarrick resigned in July over allegations of sexually abusing minors, but since then priests in the diocese of Lincoln, Nebraska, and seminarians in Boston and elsewhere have publicly accused their superiors of turning a blind eye to sexual misconduct.

The Pennsylvania grand jury met for two years, reviewed 500,000 documents from dioceses’ secret archives, and heard testimony from dozens of victims and the bishop of Erie. The report covers the dioceses of Allentown, Erie, Greensburg, Harrisburg, Pittsburgh and Scranton. Two of the dioceses — Greensburg and Harrisburg — tried to quash the grand jury investigation last year, but later backed off that stance.

The report lists each of the accused priests and documents how they were sent from parish to parish, and even sometimes out of state. The grand jury said that while the list is long, “we don’t think we got them all.” The report added, “We feel certain that many victims never came forward, and that the dioceses did not create written records every single time they heard something about abuse.”

In the Greensburg diocese, the Rev. John Sweeney was charged by the attorney general’s office with sexually abusing a boy in the early 1990s. Father Sweeney pleaded guilty this month and awaits sentencing. In the Erie diocese, the Rev. David Poulson was arrested in May and charged with sexually assaulting a boy for eight years, starting at age 8. Father Poulson has yet to enter a plea.

The Pennsylvania State Legislature has so far resisted calls to lift the statute of limitations, which has prevented childhood victims from filing civil lawsuits against the church after they turn 30. For many victims, it has taken decades to gain the courage to speak about the abuse, long past when the law would allow them to sue.

The grand jury and the attorney general strongly recommended that the statute of limitations be extended in civil and criminal cases. They recommended opening a temporary “window” that would permit older victims to file civil lawsuits against perpetrators, and the church.

The church has lobbied against any change to the statute or to open such a window, its efforts led by Bishop Ronald W. Gainer of Harrisburg, president of the Pennsylvania Catholic Conference. But abuse survivors and advocates say that in September they plan to begin a fresh campaign to press lawmakers and Bishop Gainer to drop their opposition.

“If this doesn’t start a serious debate on the elimination of the statute of limitation, there’s something seriously wrong with my fellow Pennsylvanians,” said Shaun Dougherty, now 48, who testified before the Altoona-Johnstown grand jury about being abused by a priest for three years starting at age 10.

About two dozen people named in the report petitioned the court to have their names redacted from it.

In the news conference, Mr. Shapiro, the attorney general, described the “intense legal battle” that played out over the last several months as some people named in the report appealed to the Pennsylvania Supreme Court to block its release.

“They wanted to cover up the cover-up,” he said.

Mr. Shapiro said his office would continue to fight for a full version of the report to be released with no redactions.

One example of a cover-up detailed in the report concerns the Rev. Ernest Paone, a priest who was caught molesting boys and using guns with young children in Pittsburgh. A fellow pastor intervened in 1962 to stop the police from arresting him. The district attorney at the time, Robert Masters, wrote to the diocese in 1964 to say that he had halted his investigation of the case “in order to prevent unfavorable publicity” for the diocese.

In testimony before the grand jury, Mr. Masters said that he had wanted the church’s support for his political career.

Father Paone was relocated successively to Los Angeles, San Diego and Reno in the following years, with Pittsburgh’s bishops attesting to his fitness as a priest. Among those bishops was Cardinal Wuerl, now the archbishop of Washington. He accepted Father Paone’s resignation from ministry in good standing in 2003, allowing him to collect his pension.

As of Tuesday, all six of the dioceses covered by the report had released the names of priests with allegations against them.

Bishop Gainer in Harrisburg recently ordered that the names of accused priests and of bishops who mishandled abuse cases be taken down from all church buildings in the diocese.

The report says that one of the victims who had testified before the grand jury tried to commit suicide while they were deliberating.

“From her hospital bed, she asked for one thing,” the grand jury wrote in the report, “that we finish our work and tell the world what really happened.”