The White House made its first reported policy change in wake of Sunday's massive WikiLeaks report, directing government agencies on Monday to tighten procedures for handling classified information.
The new procedures would ensure "that users do not have broader access than is necessary to do their jobs effectively, as well as implementation of restrictions on usage of, and removal of media capabilities from, classified government directives," according to a directive from the Office of Management and Budget released on Monday.
Also on Monday, a top U.S. law enforcement officer said a U.S. investigation into the source behind the leaking of thousands of secret U.S. military and diplomatic cables to WikiLeaks was ongoing.
"We have an active, ongoing criminal investigation with regard to this matter," Attorney General Eric Holder said, adding the probe was being carried out with the Department of Defense.
Holder added that WikiLeaks used the information it had obtained irresponsibly, as opposed to members of the press and news agencies.
“I think there's a real basis… to believe that crimes have been committed," he said.
U.S. military authorities detained Army Private Bradley Manning and in July transferred him from Iraq to the United States in connection with leaking classified documents to WikiLeaks. He was charged with unauthorized use and disclosure classified material relating to videos published by WikiLeaks.
He remained a person of interest in the WikiLeaks publication of tens of thousands of Afghan war-related documents.
Authorities have not said whether he is the suspect behind the publication of nearly 400,000 Iraq war military documents, or the release of more than 250,000 State Department cables WikiLeaks began publishing Sunday.
Manning was working as an intelligence analyst in Iraq at the time of his arrest and reportedly had access to classified material. Reports said the military had obtained evidence from his computer showing he had downloaded secret information.
Manning was reportedly able to access the documents following reforms after the September 11, 2001 terrorist attacks, that made it easier for classified information to be shared across government agencies.
WikiLeaks has refused to identify any sources. A spokesman for WikiLeaks, Kristinn Hrafnsson, defended the release against charges that it could endanger lives around the world.
"We have gone to great lengths to scrutinize the information ... in order to redact the names of individuals who actually may be harmed by exposure," he told CNN.
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