Pentagon says evicted Russian hackers, global cyber threat grows

U.S. Defense Secretary Ash Carter at the Defense Ministry in Seoul, South Korea, Friday, April 10, 2015. REUTERS/Lee Jin-man

PALO ALTO, California (Reuters) - The United States on Thursday disclosed a cyber intrusion this year by Russian hackers who accessed an unclassified U.S. military network, in a episode Defense Secretary Ash Carter said showed the growing threat and the improving U.S. ability to respond.

Carter cited the newly declassified incident during an address at Stanford University, in which he also warned the Pentagon was ready to help defend America's networks and to use cyber weaponry, if needed.