Several business leaders in Wallis and Futuna are being investigated for allegedly defrauding the French government of nearly five million US dollars.
Eight people are at the centre of the probe into what is being described as a swindle by an organised gang.
Four of them were taken into custody in New Caledonia but while they have been released, they are banned from returning to Wallis.
They are accused of presenting inflated bills and abusing the tax
benefits aimed at boosting investment in overseas territories.
The probe was called after the number of companies involved in public works inexplicably multiplied this year.