Defense Secretary Carter Used Personal Email

Defense Secretary Ash Carter used a personal email account to conduct government business.

The Pentagon said it happened early this year, during Carter's first months on the job.

The revelation only came after the New York Times uncovered 72 work emails from Carter's personal email address.

His press secretary said Carter admits his use of personal email was a mistake.

The news is a reminder of Hillary Clinton's email scandal, which is being investigated.

Clinton used a personal email server while secretary of state, even sending classified government material through personal emails.