Story highlights "We had talked to our French counterparts ... and we gave them a heads up," Rogers said Tuesday

Macron had been the victim of a "massive and coordinated hacking operation," his campaign team said

Washington (CNN) National Security Director Adm. Mike Rogers, who heads up US Cyber Command, said Tuesday that the US warned France about Russian cyberactivity prior to the hack of then-presidential candidate Emmanuel Macron last week.

"We had talked to our French counterparts ... and we gave them a heads up: 'Look, we are watching the Russians. We are seeing them penetrate some of your infrastructure. Here's what we've seen ... what can we do to assist?'" Rogers told lawmakers on the Senate Armed Services Committee.

"We are doing the same with our German counterparts (and) our British counterparts," he added.

Macron had been the victim of a "massive and coordinated hacking operation," his campaign team said.

Around 14.5 gigabytes of emails, personal and business documents were posted to the text-sharing site Pastebin through links to more than 70,000 files, a CNN look at the data showed.

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