The details of the transgressions and resulting disciplinary steps were not revealed; however, the NSA said in a written statement Friday it had zero tolerance for such incidents.
"NSA takes very seriously allegations of misconduct, and cooperates fully with any investigations – responding as appropriate," the statement said.
The Hill said the secretive agency had previously said any violations were unintentional, but revised that stance Friday by saying there were "very rare instances of willful violations" of its rules.
The NSA said the violations did not involve the controversial Patriot Act or the Foreign Intelligence Surveillance Act.
Sen. Diane Feinstein, D-Calif., chairwoman of the Senate Intelligence Committee, responded with a written statement saying the relatively small number of cases did not change her view that the NSA was doing its best to prevent abuses of people's privacy.