Officials are blaming Russia for a cyberattack against a Pentagon email system. Military officials Sources say the attack against the Pentagon's Joint Staff unclassified email system happened around July 25th and may have affected as many as four-thousand military and civilian employees. It's being called a "sophisticated" attack that gathered information and released it online. Officials say no classified information was stolen. While authorities say the hack came from Russia, they're not sure if it was backed by the government.