Pope Francis has denounced members of the mafia, declaring that organised crime is an "evil" that "must be fought against".
"We must say no to it," he told the crowd gathered for Mass in Calabria, southern Italy, at the weekend.
In what is being described as the Vatican's strongest statement against organised crime for over 20 years, the Pope was clear that groups involved in such activities "are not in communion with God".
The Pope was visiting Castrovillari prison in Calabria, where many of the inmates are serving sentences for mafia-related crimes. The region is notorious for being home to the 'Ndrangheta - a drug-trafficking and extremely violent crime syndicate.
He spoke to the prisoners, before travelling to Cassano all'Jonio, where a three-year-old boy, "Coco" Campolongo, was shot to death and his body burned in a torched vehicle last January. The murder was apparently incited by an unpaid drug debt - his parents and grandfather were members of the 'Ndrangheta, and his father is currently serving time in Castrovillari.
At the end of his visit, Pope Francis then addressed an audience of thousands, where he made his condemning remarks.
He accused those involved in organised-crime groups of practicing "the adoration of evil and contempt of the common good" and warned that there was no place for them in the Church.
"Those who in their lives follow this path, as Mafiosi do, are not in communion with God. They are excommunicated," he said.
He insisted that the Church would increase its efforts against the violence, noting that: "Our children are asking for it, our young people are asking for it. They are in need of hope and faith".
According to Reuters News Agency, Vatican spokesman Father Ciro Benedettini has said that Francis' declaration does not refer to a formalised excommunication, whereupon an individual is officially removed from the Church. Instead, "it was more of a direct message to members of organised crime that they had effectively excommunicated themselves," as a result of their failure to be close to God.
Benedettini added that the Pope is hoping to "isolate Mafiosi within their own communicates" and underline that they are not "men of honour" to be protected.