McCullagh said creditors of the company ranged from commercial operators to people sending personal savings abroad, and many had a long association with Forex Brokers.
"One said she'd used the firm for 17 years: This seems to be a genuine failure, but we need to do some investigation to determine what happened to the funds," he said.
The Herald understands customers of the company - which offered spot FX transactions, and offshore bank drafts and telegraphic transfers - ran into problems only recently.
One customer told the Herald while the company had proven reliable in the past, a recent transfer of funds to China did not arrive at its destination.
"These things take time, but when no one was responding to emails and then the landline and website went down, alarm bells were ringing pretty hard," the customer said.
The customer said they had filed complaints with the Financial Markets Authority.
A spokesman for the FMA they had received three recent complaints about Forex Brokers, but the company offered services - spot foreign exchange transactions - that did not fall under its regulatory umbrella.
The company's website, until being taken offline last week, said the company was founded in August 1995 "with the goal of providing a higher standard of service delivery".
Forex Brokers' founding and sole director Russell Maher had said on his website: "I have over 20 years experience in the foreign currency industry and will combine this experience with an extremely high level of business integrity and customer service ... I would like the opportunity to partner with you to professionally manage your forex needs. Feel free to contact me to discuss your particular requirements."
Maher could not be contacted yesterday by the Herald.