Catholic priests carry photographic identification signed by their bishop, the church has advised, after an alleged fake cleric was arrested in Mid-Ulster.
The 56-year-old man was detained as part of a fraud investigation following reports that an individual was claiming to be a priest.
Police said he was targeting "vulnerable" older people living in rural areas.
While it remains unclear what specific area the victims live in, a spokesman for the Diocese of Derry, which covers parts of Mid-Ulster, has appealed to parishioners to exercise care.
"In light of this incident, we want to remind people that only clergy known to them will engage with them," the spokesman said.
"Like companies such as NIE and Northern Ireland Water, priests carry ID, which has a photograph on it and it is signed by the bishop.
"This is issued on an annual basis.
"People can always ask to see this ID from a priest calling at their door, it will be shown to them if they are unsure.
"All priests will carry these IDs signed by the bishop, they will be happy to show this to those who ask for it.
"If people have concerns about someone who has come to their door, they should not engage with them."
Police have also urged people who have been asked to give money to someone they believe to be a priest to contact them.
Detectives from the PSNI's criminal investigation department arrested the man in the Mid-Ulster area on suspicion of fraud by false representation and fraud by abuse of position.
A PSNI spokesperson said the arrest followed a probe into three reports of a male claiming to be a serving priest "fraudulently obtaining money from vulnerable older people living in rural communities".
Police said the man was later released on bail to allow for further police enquiries.
The spokesman added: "I would encourage anyone else who feels they have had a similar experience or is concerned that they have given money to an individual they believed to be a priest, to get in touch with us so we can examine your report and take all the necessary steps to investigate."
