|Putin and Le Pen in Moscow|
Macron's team had earlier announced that the candidate had lodged an official complaint over "the spreading of false information" to try to influence the result of an election.
The complaint was filed the morning after a memorable live TV debate between the two presidential election candidates.
During one particularly heated exchange in a debate marked by insults and invective the pair argued about the legal issues they faced.
After Macron said it wasn’t him that was under investigation by police, referring to the fake jobs allegations facing Le Pen, the far right candidate replied: “I hope we don’t discover you have an offshore account in the Bahamas.”
Macron warned her that her suggestion was "defamation".
Judicial sources told AFP prosecutors in Paris had opened a probe following the complaint from Macron, which comes three days before Sunday's presidential run-off vote.
A source close to the case told AFP, the complaint targets "information that circulated Wednesday night on the internet" (probably from Russian sources) alleging tax evasion in the Bahamas.
Read more: Macron launches legal suit after Le Pen repeats 'Bahamas bank account' rumours - The Local