Pope Francis on Sunday begged forgiveness for the multitude of abuses suffered by victims in Ireland at the hand of the church over decades as he concluded a tour of the once deeply Catholic country watched by parishioners and protesters.

After meeting privately with abuse victims on Saturday on the first papal visit to Ireland in almost four decades, Francis apologised to mothers estranged from their children in church-run homes, children abused by priests and those exploited in religious schools, calling it a "state of shame."

"To survivors of abuse of power, conscience and sexual abuse, recognising what they have told me, I would like to put these crimes before the mercy of the Lord and ask forgiveness for them," Francis told a mass attended by more than 100,000 people at Dublin's Phoenix Park.

"We apologise for some members of the hierarchy who did not take care of these painful situations and kept silent."

Years of sexual abuse scandals have shattered the credibility of the Church which four decades ago dominated Irish society. In the past three years, Irish voters have approved abortion and gay marriage in referendums, defying the Vatican.

Pressure on the pope over church abuse increased elsewhere on Sunday when a former top Vatican official accused Francis of having known of allegations of sex abuse by a prominent US cardinal for five years before accepting his resignation last month.

A woman attends a vigil at the site of the Tuam babies graveyard where the bodies of 796 babies where uncovered at a site of a former catholic home for unmarried mothers and their children in Tuam. Photo: ReutersA woman attends a vigil at the site of the Tuam babies graveyard where the bodies of 796 babies where uncovered at a site of a former catholic home for unmarried mothers and their children in Tuam. Photo: Reuters

The declining influence of the Catholic Church has been demonstrated by crowds far smaller than those that met Pope John Paul II during the last Papal visit in 1979, when more than three-quarters of Ireland's population turned out.

While 500,000 people snapped up tickets to see Francis say mass, local media quoted police recording the numbers as estimating some 130,000 arrived in the rain at the same spot where Pope John Paul II stood 39 years ago. Tens of thousands more prayed with him at the Knock shrine in the west of Ireland.

"False dawns"

Francis, facing sexual abuse crises in several countries, wrote an unprecedented letter to all Catholics last week asking each one of them to help root out "this culture of death" and vowing there would be no more cover ups.

Some who turned out on the misty morning in Knock, where a group of locals in 1879 said they saw an apparition of the Virgin Mary, said Francis should be given time to deal with the abuse issues that have rocked the Church for decades.

"People have to give this man a chance, he's trying his best," said Carmel Lane, who travelled from County Longford in the midlands.

One Irish survivor of clerical abuse who met the pope on Saturday, Paul Redmond, told Reuters the strong language used by Francis at the meeting gave him hope that something might be shifting in the church.

People protest the Pope's visit in Dublin. Photo: ReutersPeople protest the Pope's visit in Dublin. Photo: Reuters

Ireland's Deputy Prime Minister, Simon Coveney, also said Francis' promise of decisive action on abuse was very welcome, but told broadcaster RTE that "people will clearly be watching now after this visit to see what actions follow."

"Very, very painful"

However thousands of people joined survivors, their families and supporters at an event elsewhere in Dublin as the pope said mass to stand in solidarity with those who had suffered.

"It (the visit) has been very, very painful," said Graham Mills, 52, who was sexually abused as a child by a member of the Christian brothers religious order and travelled from Northern Ireland to join the protest.

"I think Pope Francis is probably a very decent human being. But yesterday I was very disturbed by the big celebration for him knowing the lives that have been destroyed."

Grammy Award-nominated Irish singer Hozier performed his hit Take Me To Church as abuse survivors addressed the crowd who were then asked to walk in silence to the last of Ireland's former notorious Magdalene laundries that remains standing.

Hundreds also gathered in the western town of Tuam for a vigil at the site of a former church-run home for unwed mothers where an unmarked grave with the remains of hundreds of babies stored in underground chambers was found in 2014.

"My mother's baby died in there at 6-years-old, it's an obscenity. We're standing on a place where unburied babies, 796 of them, are in a septic tank," said Annette McKay, 64, who travelled from Britain for the vigil.

"Your (Francis') church did this to 796 innocent children and their mothers. Tell me how you are going to change this."

Baby socks hang above a list of the children buried at a Catholic home in Tuam. Photo: ReutersBaby socks hang above a list of the children buried at a Catholic home in Tuam. Photo: Reuters

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