A private college that closed suddenly last November is alleged to owe more than €500,000 to international students.
The students enrolled at the college are from India, The Philippines, Bangladesh and other developing countries.
The Irish Council for Overseas Students has gathered documentation from more than 150 students.
They are all owed fee refunds of up to €5,000 from Shelbourne College for courses that they were never able to begin.
Last November, RTÉ News reported that the college owed tens of thousands of euro in refunds to more than 50 students in developing countries.
In the following days it closed down.
Since its closure the Irish Council for Overseas Students and RTÉ have been contacted by many more students who have provided documentation showing that they are in the same situation.
Based on the documentation its received, ICOS now reckons that upwards of 150 students in India, Nepal, Pakistan, Bangladesh, The Phillipines, Sri Lanka and Vietnam are owed money.
Irish immigration regulations oblige students in these countries to pay fees to a college before they apply for a visa to allow them to come here to study.
If their visa application is rejected the college is legally obliged to return the money.
The majority of the 150 cases documented by ICOS had their visa applications rejected earlier this year.
They have been trying unsuccessfully since last June to have their fees returned.
Others still have visa applications pending, but the college has now closed down.
Attempts by students to contact Shelbourne College have been unsuccessful.
Shelbourne College is one of a number of colleges approved by the Irish Government for visa purposes.
The Department of Justice in November told RTÉ News that any breach of the requirement to refund fees to students was regarded as a very serious violation.
It said it would not hesitate to remove such a college from its register if the violations were not resolved.
Today Shelbourne College remains listed on the State's register of approved colleges.
Data received by RTÉ News from the Department of Justice shows that over the past year and a half 85% of all visa applications related to the college were rejected by immigration authorities.
This compares to an overall rejection rate of 15%.
The Department of Justice said it could not comment on specific allegations.
It said if a private business was involved in defrauding a person then this was a criminal matter that should be reported to the gardaí.
However students and their families have told RTÉ News that they have had great difficulty in getting the gardaí to take their complaints seriously.
In a statement the Department of Justice said it was open to the idea of establishing a protected account.
The protected account would be an escrow, which would hold money safely on behalf of students pending visa approval or otherwise.
The Department said it had approached the banking sector about this in the past but that at the time none was able to offer this kind of product.
The last listed directors of Shelbourne College are Adnaan Wahala and Catherine Laffey.
Since the college closed RTÉ news has tried on numerous occasions to contact Mr Wahala, but with no success.
The Companies Registration Office had received notice of Catherine Laffey's resignation from Shelbourne College last November.
Ms Laffey has declined to do a recorded interview with RTÉ News.
In telephone conversations she has said she had no involvement with the company's finances.