Hackers with connections to the Russian government played a role in an effort to damage centrist French politician Emmanuel Macron’s presidential campaign by hacking and leaking emails and documents ahead of the election, according to two U.S. intelligence officials.

Separately, Admiral Mike Rogers, the director of the U.S. National Security Agency, told the Senate Armed Services Committee on Tuesday that Washington became “aware of Russian activity” in the French election long before purported campaign emails were leaked two days before Sunday’s vote that Macron won in a landslide.

“We gave them a heads up … “Look, we’re watching the Russians, we’re seeing them penetrate some of your infrastructure’,” Rogers said.

The two officials and four others familiar with intelligence agency findings acknowledged that they have not found conclusive evidence that the Kremlin ordered Russian intelligence agencies to do the hacking, or that they directed it.