Paedophile priest Malachy Finnegan has been linked to a string of child abuse allegations, understood to have taken place at St Colman's College in Newry and later in the parish of Clonduff in Co Down.
The scandal surrounding the cleric, who died in 2002, emerged in February, four months after the Church agreed a landmark financial settlement with one of his victims.
Finnegan worked at St Colman's College in Newry from 1967 to 1987, and spent his last 11 years at the boys' grammar school as president. He moved to Clonduff as parish priest in January 1988.
The Diocese of Dromore was aware of 10 allegations against the priest before a BBC Spotlight programme brought his crimes into the public arena last month. At least three more complaints have been passed to the Church since it aired and the PSNI has received at least eight reports in recent weeks.
Dr John McAreavey stood down from his post as Bishop of Dromore on March 1 after coming under fire for his handling of the case. The bishop, who took up his position in 1999, was criticised when it emerged he said mass with Finnegan in 2000 and officiated over his funeral mass two years later, despite knowing about allegations against the priest. Dr McAreavey apologised last month for what he called "an error of judgment".
However pressure mounted, including criticism from a number of parents in the diocese who voiced concerns about his presence at their children's upcoming confirmation ceremonies, and he resigned, leaving Canon Liam Stevenson to take up the reins until a permanent replacement is found.
The Diocese of Dromore has said the first report about Finnegan came to the Church in 1994.
A second report was made to police in 1996, although the victim, who was just 17 at the time, did not submit a formal complaint. Two years later, in 1998, he brought his allegation to the diocese. The PSNI said it did not receive a report from the diocese relating to Finnegan until 2006.
The board of governors at St Colman's condemned the abuse inflicted on pupils by Finnegan and ordered all images of him to be removed from the school.
In 2011 Dr McAreavey said he welcomed an independent audit into allegations against priests in the diocese between 1975 and 2011. He also asked the auditors to review the cases of three deceased priests, including Finnegan.
In response to the revelations, the PSNI has set up a dedicated unit to investigate "clerical and institutional abuse" involving the priest. St Colman's College has pledged to "cooperate fully".