An investigating grand jury has found that for decades several priests in the Roman Catholic Diocese of Altoona-Johnstown sexually abused hundreds of children and two bishops acted to cover up the acts, but the Pennsylvania Office of Attorney General said charges will not be forthcoming.

The 37th Statewide Investigating Grand Jury released a 147-page report Tuesday outlining the findings from a two-year investigation led by the Attorney General’s Office, which included the uncovering of a “secret archive” in the diocese’s office “filled with documents detailing children being sexually violated by the diocese’s own members,” a statement from the ­office said.