US officials say naming North Korea as responsible for Sony hack part of government response

A top Justice Department official says the U.S. government is increasingly committed to publicly calling out foreign governments when there's evidence they're responsible for cyber-attacks.

John Carlin, head of the Justice Department's national security division, said once the government decided North Korea was responsible, officials thought it was important to say so.

He says that decision, along with last year's indictment of five Chinese military officials, is part of a trend by the U.S. government to publicly identify culprits as part of a broader effort toward deterrence.

Carlin appeared at a cybersecurity conference at Fordham University in New York, where he and other Obama administration officials reaffirmed their conclusion that North Korea was responsible for the hack in the face of skepticism from some independent experts.