Regis Duvignau / Reuters

French presidential candidate Emmanuel Macron was the victim of a “massive, co-ordinated hacking” on Friday, BBC reports. According to Macron’s campaign staff, a number of internal documents were leaked on a file-sharing website late Friday night, less than 48 hours before the election.

The front-runner’s staff said some of the leaked files were fake, while others were authentic, in what they believe is an attempt to introduce “doubt and misinformation” into the campaign. The documents contained emails and financial data, but demonstrated nothing more than the normal workings of a presidential campaign, the staff said.

“The leaked files were obtained several weeks ago by hacking personal and professional email accounts of several officials of the movement,” reads a campaign statement. They added: “The seriousness of this event is certain and we shall not tolerate that the vital interests of democracy be put at risk.”

Friday’s hacking appears to have been timed to coincide with the start of the official ban on election campaigning, which is now in place. The ban will remain effective until polling stations close late Sunday, and forbids commentary that might influence the election. As a result, an interior ministry official declined to comment on news of the hacking.

Cyberattacks have become increasingly common in today’s international political landscape. On Tuesday, former U.S. presidential candidate Hillary Clinton pointed to the untimely release of her campaign chairman John Podesta’s emails—allegedly the work of Russian hackers—as one of the reasons she lost the 2016 U.S. election. “Russian WikiLeaks raised doubts in the minds of people who were inclined to vote for me but got scared off—and the evidence for that intervening event is, I think, compelling [and] persuasive,” Clinton said. Numerous intelligence agencies have similarly concluded that Russian interference likely swayed the election’s outcome.

As with the U.S. election, the source of Friday’s hacking—and that source’s motivation—are as concerning as the contents of the leaked material. In the past, Macron’s staff has complained of hacking attempts, pointing to Russia as a potential source. In April, the staff said they were the victim of hackers attempting to steal email credentials, though no internal campaign data was made public. The Kremlin denied any involvement.

The development also comes a day after the French prosecutor's office opened an investigation into a complaint by Macron that his campaign was being targeted by fake news that aimed to influence the French election. Marine Le Pen, the far-right candidate who is Macron’s rival in the election, alleged in their sole presidential debate Wednesday that he held an offshore account. Macron, who denies the claim, pointed to her financing by Russian banks.

Prior to the reported hacking, Macron was expected to clench the presidency by a wide margin. An Elabe poll after Wednesday’s debate found 63 percent of viewers saying they found Macron more convincing; 34 percent favored Le Pen’s performance.

On Thursday, former U.S. President Obama announced his support for Macron. While Obama said he is “not planning to get involved in many elections” moving forward, he saw his endorsement of Macron as necessary, seeing as “the success of France matters to the entire world.”

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