Hundreds of children in the Altoona–Johnstown Diocese in Pennsylvania were abused by at least 50 different priests or religious leaders over six decades, while two Catholic bishops covered up their crimes, according to a scathing report by a Pennsylvania state investigative grand jury.

The 145-page report, which is based on a two-year investigation of several handwritten notes, letters and documents detailing children being abused by members of the church, shows that Bishop James Hogan and his successor Bishop Joseph Adamec knew of the allegations and did nothing.

“This grand jury … found that the actions of Bishops James Hogan and Joseph Adamec failed to protect children entrusted to their care and guidance,” the report said. “Worse yet, these men took actions that further endangered children as they placed their desire to avoid public scandal over the wellbeing of innocent children. Priests were returned to ministry with full knowledge they were child predators.”

Hogan led the diocese of just over 94,000 Roman Catholics from 1966 to 1986 before his death in 2005. Adamec, who took over from him, retired in 2011.

Revelations that some priests had habitually sexually abused children and that bishops had systematically covered up these crimes first came to light in 2002 when the Boston Globe reported widespread abuse in the Boston Archdiocese. The latest report comes just days after the Hollywood movie “Spotlight,” which chronicled the Boston Globe investigation, won an Oscar for best picture.

“A conspiracy of silence has deep roots in the Altoona-Johnstown Roman Catholic diocese, and in church law itself, where ‘secret archives’ are used to hide scandalous information, such as sex abuse by priests,” the report said. “Nationally, the sex scandal that started in Boston and spread from coast to coast, has torn down that wall of silence. Now, everyone’s talking, either in court or in the court of public opinion.”

The report contains explicit details of scores of attacks and names perpetrators, many of whom have since died.

In one of the more egregious cases, Francis McCaa — a cleric who spent nearly 40 years in the ministry and died in 2007 — was found to have groped and fondled at least 15 boys aged 8 to 15 between 1961 and 1985, while serving as a parish priest at the Holy Name parish in Ebensburg, Pennsylvania.  At least one of his victims committed suicide.

“Father Francis McCaa was a monster. ... Yet, McCaa was highly respected within the diocese of Altoona-Johnstown and was given the designation of Monsignor as a sign of respect and trust,” the report said. “Unlike his victims who sought to be saved from McCaa’s torment, Hogan enabled it. Bishop Hogan knew that Francis McCaa had engaged in sex acts with multiple altar boys by 1985. ... Within a year of Hogan’s meeting with the district attorney’s office, McCaa was reassigned as a hospital chaplain in Martinsburg, West Virginia. Hogan provided McCaa a glowing recommendation for his new post.”

Many of the surviving priests were still serving parishes at the time the investigation began, Pennsylvania State Attorney General Kathleen Kane, whose office made the report public Tuesday, said.

“The Grand Jury has learned that euphemisms like ‘sick leave’ and ‘nervous exhaustion’ were code for moving offending priests to another location while possible attention to a recent claim of child molestation ‘cooled off,’” the report stated.

However, none of the members of the clergy who committed the criminal acts documented in the report can be prosecuted as the statute of limitations has expired.

“This is by no means the end of our investigation. We will continue to look at this matter and consider charges where appropriate, which is why it is so important for those with information to come forward,” Kane said. “At the very least we must continue to shine a light on this long period of abuse and despicable conduct.”