Advocates for clerical sex abuse victims have expressed outrage that a priest accused of sexually abusing deaf children in Italy wasn't sanctioned by the Vatican, and allegedly went onto abuse children in Pope Francis' native Argentina.

Argentine police arrested Nicola Corradi Monday. He and others are accused of abusing at least eight children at a school for youths with hearing disabilities in Mendoza province.

BishopAccoutability.org, an online resource about clerical abuse, said Thursday that Italian survivor groups told the Vatican in 2008 and 2014 about Corradi and others accused of molesting children at a school for the deaf in Verona.

The group says that Corradi was able to repeat the abuse of "defenseless children who could neither hear nor speak" because Francis and other church authorities didn't stop him.