A victim of a paedophile priest in Chile has revealed he wrote to the Pope in 2015 about an alleged cover-up after Francis denied getting evidence.
Juan Carlos Cruz, a victim of cleric Fernando Karadima in the 1980s, accused fellow priest Juan Barros of witnessing the abuse and doing nothing.
The Pope caused outrage after a visit to Chile last month by defending Bishop Barros, who was made a bishop in 2015.
The Vatican refused to comment on the letter when approached by BBC News.
Pope Francis has said in the past that dealing with abuse is vital for the Church’s credibility and perpetrators must face “sanctions”.