PARIS, FRANCE (REUTERS) – Leading French presidential candidate Emmanuel Macron’s campaign said on Friday night (May 5) that it had been the target of a “massive” computer hack that dumped its campaign e-mails online one and a half days before voters choose between the centrist candidate and his far-right rival, Marine Le Pen.

As much as nine gigabytes of data were posted on a profile called EMLEAKS to Pastebin, a site that allows anonymous document sharing. It was not immediately clear who was responsible for posting the data or if any of it was genuine.

In a written statement, Macron’s political movement En Marche! (Onwards!) confirmed that it had been hacked.

“The En Marche! Movement has been the victim of a massive and co-ordinated hack this evening which has given rise to the diffusion on social media of various internal information,” the statement said.

An interior ministry official declined to comment, citing French rules that forbid any commentary liable to influence an election, which took effect at midnight on Friday (2200 GMT).

Former economy minister Macron’s campaign has previously complained about attempts to hack its e-mails, blaming Russian interests in part for the cyber attacks.

Researchers with security firm Trend Micro in Tokyo, said they had found evidence that the spy group, dubbed “Pawn Storm”, targeted the Macron campaign with email phishing tricks and attempts to install malware on the campaign site at least in four separate attempts.