US Defence Secretary Ash Carter admits personal email 'mistake'
US Defence Secretary Ash Carter has admitted that using personal email to conduct some government business was a "mistake".
In an interview with CBS, Mr Carter said it was "a mistake and it's entirely my own".
Democratic presidential candidate and former Secretary of State Hillary Clinton did the same thing, prompting an FBI investigation.
He used personal email during his first two months as defence secretary.
"I have to hold myself to absolutely strict standards in terms of cybersecurity and doing things that are appropriate. I didn't in this case," said Mr Carter.
The New York Times reported that it obtained 72 work emails Mr Carter sent or received from his non-work email account.
Some emails were about speeches and media appearances, the Times reports.
Mr Carter's press secretary Peter Cook said Mr Carter has stopped using his personal email for any work purposes.
"The secretary believes that his previous, occasional use of personal email for work-related business, even for routine administrative issues backed up to his official account, was a mistake," he said in a statement.
Mr Carter "takes his responsibilities with regard to classified material very seriously," Mr Cook said.
He did not say whether it was a violation of Pentagon policy.
Senator John McCain said it was "hard to believe that Secretary Carter would exercise the same error in judgement" after the news of Ms Clinton's personal email use broke, drawing much scrutiny.
The Senate Armed Serviced Committee is reviewing the emails to make sure sensitive information was not compromised.