The Serious Fraud Office says investors have lost millions of dollars in a Ponzi scheme, also known as a pyramid scheme, operating in New Zealand.
The head of fraud and corruption investigations, Nick Paterson, says the SFO will make an arrest on Thursday in the case.
Mr Paterson says the investigation began after the Companies Registrar received a complaint about a suspected Ponzi scheme.
This is a fraudulent investment which pays out investors from money paid by subsequent investors, rather than profits.
Mr Paterson says he is unable to give any more details before the arrest is made.