Defense officials knowledgeable about the campaign have said that U.S. Cyber Command is going after individual Russian operatives, notifying them that they have been identified and are being monitored.
The officials, however, have refrained from revealing how many operatives are being targeted or how they are being contacted.
The cyber operation is only one of multiple initiatives being undertaken to safeguard U.S. elections from Russian influence.
USCYBERCOM has also sent teams to Europe to help allies defend their networks from Russian hacking.
Meanwhile, social networking services are in the process of removing fake users and accounts that spread misinformation.