A manhunt is underway for what government officials say is a traitor inside the Central Intelligence Agency.

The CIA and FBI are conducting a joint investigation into one of the worst security breaches in CIA history. The breach exposed thousands of top-secret documents that described the agency's tools used to penetrate smartphones, smart TV's and computer systems.

Sources tell

. they are looking for an insider, either a CIA employee or contractor who had physical access to the materials that were published by the anti-secrecy organization, WikiLeaks.

Much of the material was classified and stored in a highly secure section of the CIA, but sources tell CBS News hundreds of people would have had access to the material. CBS News reports investigators are going through those names.