AP Exclusive: US said not responsible for cyberattacks that crippled North Korea's Internet

Two senior U.S. officials tell The Associated Press that the U.S. government is not responsible for the sustained electronic attacks that crippled North Korea's Internet infrastructure last month.

Those attacks happened just after President Barack Obama promised that his administration would respond to the hacker break-in at Sony Pictures Entertainment Inc.

The Obama administration has been coy about whether it caused North Korea's outage, which affected all of that nation's Internet connections starting the weekend of Dec. 20. But the two officials acknowledge to the AP that it is not a U.S. operation. They spoke on condition of anonymity because they are not authorized to openly discuss the issue.

It is not immediately clear even within the Obama administration whether rogue hackers or other governments disrupted North Korea's networks.