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France's election is the latest victim of Russian hacking. That's according to the NSA.

After US intelligence agencies agreed Russia was behind the 2016 presidential election hacking, both Federal Bureau of Intelligence Director James Comey and former Director of National Intelligence James Clapper warned that Russian hackers would be back to influence future elections.

The warning rang true during France's presidential election, National Security Agency Director Mike Rogers revealed on Tuesday. Rogers was testifying at a Senate Armed Services committee hearing, as lawmakers look to establish a policy on how to respond to cyberattacks.

The NSA director and US Cyber Command leader told the committee that the US was monitoring Russian activity and saw hackers attempt to break into France's election infrastructure.

"We had talked to our French counterparts prior to the public announcements of the events publicly attributed this past weekend and gave them a heads up. 'Look, we're watching the Russians. We're seeing them penetrate some of your infrastructure,'" Rogers said during the hearing. "Here's what we can do to try to assist."

On Friday, two days before France's election, hackers leaked hordes of emails from candidate Emmanuel Macron's campaign in a last-minute attempt to sway voters. It didn't work. Macron won the presidency on Sunday. It had been unclear who was behind the leak, but Russia was a prime suspect.

"We've known for some time that the Russians run fairly robust information operations in Europe, and have for many years," Michael Daniel, the president of the Cyber Threat Alliance, said in an email.

Despite the failed influence campaign in France, it hasn't stopped Russian hackers from trying in other nations, Rogers said.

"We're doing similar things with our German counterparts, with our British counterparts, they have an upcoming election sequence," the NSA director said.

The Russian Embassy in the US didn't immediately respond to a request for comment. The Kremlin has previously denied any involvement with hacking efforts to influence the world's elections.

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