Investigators have detained Pascale Haiti, who is the partner of the French Polynesian veteran politician, Gaston Flosse, as part of the Tahiti probe of the OPT telecommunications company.
Pascale Haiti, who is a former assembly member and minister, is suspected of having played a role in last week's alleged attempt in Papeete to destroy evidence pertinent to the probe.
She was detained in Paris and according to new information she can be held for two weeks before she is transferred to Tahiti where she could be questioned and put into prison.
A computer technician was arrested last weekend over the same incident.
Mr Flosse's housekeeper and his party's treasurer, who had also been questioned, have been released.
Four other people have been in the Tahiti jail in so-called provisional detention for up to four months as part of the probe.
Next week, Mr Flosse is expected to be formally charged over the affair, in which he is alleged to have received two million US dollars in kickbacks for giving public sector contracts to a French advertising agency.
This morning, he was convicted in another court case and given a suspended jail term.
He is also set to lose his seat as French senator and French Polynesian assembly member as a result, which observers say is the end of his political career.