An investigation into sexual abuse in the French Catholic Church has found that an estimated 216,000 children were victims of abuse by clergy since 1950, said Jean-March Sauve, head of the commission that compiled the report.
The revelations in France are the latest to rock the Catholic Church, after a series of sexual abuse scandals around the world, often involving children, over the past 20 years.
The abuse was systemic, Mr Sauve said at a public, online presentation of the report, adding that the church had shown "deep, total and even cruel indifference for years," protecting itself rather than the victims.
The commission was established by Catholic bishops in France at the end of 2018 to shed light on abuses and restore public confidence in the church at a time of dwindling congregations.
It has worked independently from the church.
Mr Sauve said the problem was still there. He added that the church had until the 2000s showed complete indifference to victims and that it only started to really change its attitude in 2015-2016.
He said the commission itself had identified around 2,700 victims, but that a wide-ranging study by research and polling groups had estimated that there had been around 216,000 victims.
The number could go up further to 330,000, when including abuse by lay members.
Speaking just after Mr Sauve at the presentation of the report, the archbishop of Reims and head of the French conference of bishops, Eric de Moulins-Beaufort, spoke of shame, asked for forgiveness and promised to act.
Pope Francis expressed his "great sorrow" for the victims of sexual abuse by French Catholic clergy, a Vatican spokesman said.
He said the pontiff had learned "with pain" of the report's contents, adding: "His thoughts turn first to the victims, with great sorrow for their wounds and gratitude for their courage in speaking out."
The Catholic Church's teaching on subjects such as sexuality, obedience and the sanctity of the priesthood helped created blind spots which allowed sexual abuse by clergy to happen, Mr Sauve said, adding that the church needed to reform the way it approached those issues to rebuild trust with society.
The church must take responsibility for what happened, the commission said, and ensure reports of abuse are transmitted to judicial authorities.
It must also provide victims with adequate financial compensation, "which, despite not being sufficient (to address the trauma from sexual abuse), is nonetheless indispensable as it completes the recognition process."
It added a list of recommendations that included systematically checking the criminal record of any person assigned by the church to be in regular contact with children or vulnerable people, and providing priests with adequate training.
There have been around 2,900-3,200 suspected paedophiles in the French Church over the last 70 years, Mr Sauve said.
"You are a disgrace to our humanity," Francois Devaux, who set up victims' association La Parole Liberee, told church representatives at the public presentation of the report, before Mr Sauve took the floor.
"In this hell there have been abominable mass crimes ... but there has been even worse, betrayal of trust, betrayal of morale, betrayal of children," Mr Devaux said, also accusing the church of cowardice.
He thanked the commission, saying he hoped the report would prove a turning point: "You finally bring victims an institutional recognition of the responsibility of the church."
In June, Pope Francis said the Catholic Church's sexual abuse crisis was a worldwide "catastrophe".
Since his election in 2013, he has taken a series of steps aimed at wiping out sexual abuse of minors by clerics.
This year, he issued the most extensive revision to Catholic Church law in four decades, insisting that bishops take action against clerics who abuse minors and vulnerable adults.
But critics accuse Pope Francis of responding much too slowly to the sex abuse scandals, of failing to empathise with victims and of blindly believing the word of his fellow clergy.