Nightly News | June 28, 2013
>>> more tonight on a story we broke last year. about retired marine corps general james cartwright , the country's second-ranking military official and how he's being investigated about leaking information about a secret u.s. cyber attack against iran. the senior investigative correspondent michael isikoff continues his reporting tonight.
>> reporter: general cartwright retired after nearly 40 years of service. and cartwright continued to serve. appointed to the defense policy board , an elite pentagon advisory panel with top secret security clearance . last january, cartwright resigned out of the blue, a board member tells nbc news. the fbi was already investigating cartwright, suspecting him of leaking highly classified secrets on about a covert u.s. cyber attack , using a computer virus called stuxnet on iran's nuclear program. his resignation was unrelated according to a cartwright spokesman. his attorney says "general jim cartwright is an american hero who served his country with distinction for four decades. any suggestion that he could have betrayed the company that he loved is preposterous." eric holder wasn't talking.
>> can you comment on the investigation of james cartwright ?
>> no, i can't are he w.
>> reporter: he was a savvy top aide. his real mark, in developing the country's future military needs in cyberspace.
>> a crucial voice communicating the opportunities and dangers in terms of cyber wars .
>> i'm not advocating starting a war on the internet.
>> reporter: is there evidence to bring criminal charges against the four- star general that led the u.s. military into cyber warfare ? michael isikoff , nbc news, washington.