The United States has been charged with launching a cyberattack against France -- a claim the U.S. government has categorically denied.

According to L'Express, a French news outlet, sources with knowledge of a cyberattack that occurred in May have said the U.S. was behind the attack. The news outlet claims that the attack occurred a few days before the country's presidential election and targeted "the team of [former French President] Nicolas Sarkozy."

L'Express' sources say the hackers worked their way through Sarkozy's team to attack his closest advisers. In order to climb that ladder, the hackers kicked off their efforts on Facebook, identifying people who were in some way linked to Sarkozy. From there, they were sent e-mails that contained a link leading to a fake website that replicated the Elysse Palace's own page. After the page asked for a username and password, the advisers obliged, and their information was stolen.