Possible financial irregularities at the Rush-Lusk Credit Union in north Co Dublin, where it is reported that €700,000 has disappeared from its accounts, are being investigated by gardaí.
The Central Bank has also confirmed it is working with accountancy firm Grant Thornton, which has been tasked with conducting a review of the accounts.
The board of Rush Credit Union has said the external review process is almost complete and Grant Thornton is preparing a report for the board.
The credit union has written to its members and it is reported that they have been told to check their balances following the suspected fraud.
In a statement the Irish League of Credit Unions said: "The credit union has identified an issue.
"As the matter is currently being investigated we cannot comment in any great detail other than to say that the credit union is working extremely hard to ensure that this matter is dealt with swiftly.
"The credit union has written directly to members on this issue. We would like to reassure members that no credit union funds will be affected by the incident and that the credit union is fully insured to deal with such matters.
"Operations at Rush Credit Union have not been disrupted and members can do business with the credit union in the usual way."
A Central Bank spokesperson has also urged members to use the credit union in the usual way.
