French presidential hopeful Emmanuelle Macron’s team confirmed that it suffered a massive hacking attack after a trove of internal documents was released online just a day before the final round of elections.

On Friday evening, a profile called EMLEAKS posted a nine-gigabyte leak to Pastebin, a web application where users can store plain text.

WikiLeaks posted a link to Pastebin on Twitter, saying that the release in question “contains many tens of thousands of emails, photos, attachments up to April 24, 2017.”

However, the group denied being involved in the leak, saying only that it is verifying the information.

Update: #MacronLeaks contains many tens of thousands emails, photos, attachments up to April 24, 2017--around 9Gb in total — WikiLeaks (@wikileaks) May 5, 2017

Macron’s political movement, En Marche!, has released a statement confirming that the candidate and his campaign team were hacked.

“The En Marche movement has been a victim of a massive and coordinated hacking attack leading to the spreading this evening on social media of internal information of a diverse nature (emails, documents, contracts),” the statement said.

According to the team, “those circulating these documents are adding many false documents to authentic documents in order to sow doubt and disinformation.”

The release came “in the last hour of the official campaign” and this hack is “clearly a matter of democratic destabilization,” the statement added.

“Throughout the campaign, En Marche! has constantly been the party the most targeted by such attempts, in an intense and repeated fashion. The aim of those behind this leak is, all evidence suggests, to hurt the En Marche! party several hours before the second round of the French presidential election,” it continued.

The statement stressed that the documents “arising from the hacking are all lawful” and show the “normal functioning” of Macron’s presidential campaign.

Outgoing French President Francois Hollande told AFP that the hacking attack "will not be left without a response."

In the meantime, the presidential election commission has confirmed that it is aware of the hack, but urged the media to be cautious about publishing the details.

Recommandation aux médias suite à l'attaque informatique dont a été victime l'équipe de campagne de @EmmanuelMacronpic.twitter.com/LaLA1hgXYk — CNCCEP (@cnccep) May 5, 2017

“It [the commission] asks media, and in particular [news] websites, not to report on the content of this data” as distribution “of false information” may lead to criminal charges, it said.