Pope Francis has told members of the Mafia in Italy, where many go to Church and worship openly, that they cannot call themselves Christians because they "carry death in their souls".
The pope's improvised words on Wednesday (local time) before tens of thousands of people at his weekly general audience in St Peter's Square was his strongest attack on organised crime in nearly four years.
"So we don't have to go far, let's think about what happens right here at home (Italy)," he said while speaking generally about "fake Christians" who are corrupt while pretending to be righteous.
"[What about] the so-called Christian Mafiosi," he said.
"They have nothing at all in them that is Christian. They call themselves Christians but they carry death in their souls and inflict it on others."
Many members of organised crime groups in Italy, such as Sicily's Cosa Nostra and Calabria's 'Ndrangheta, see themselves as part of a religious, cult-like group.
Particularly in smaller towns and cities in the south, they take part in Catholic sacraments, go to church and in some cases have also found complicity by some churchmen.
The town of Oppido Mamertina in the Calabria region made headlines in 2014 when locals carrying a statute of the Madonna in a traditional religious procession diverted its route to pass by the home of local mob boss who was infirm.
They paused before the boss' house and tilted the statue slightly as if to kneel in a sign of respect toward the clan boss.
When Pope Francis visited the Calabria region the same year, he accused organised crime members of practising "the adoration of evil" and said Mafiosi excommunicate themselves from the Church by their actions.
At the audience in St Peter's Square on Wednesday, Francis asked the faithful for prayers for Mafiosi, "so that the Lord touches their souls".