Pfc. Bradley Manning was charged in June for handing over classified data to the Web site WikiLeaks. His leaked video showed a U.S. military helicopter firing on what turned out to be a photojournalist working in Iraq.
The U.S. Army announced that it had custody of Manning while it investigated the source of a massive leak of classified information on the Afghan war, CNN reports.
The Wall Street Journal reported Thursday that investigators said they uncovered clear evidence linking Manning to the case.
The Journal said it was unclear what evidence investigators had, though authorities with the FBI were working the case to probe a possible civilian connection.
Top military brass reacted with outrage to the leak, accusing Julian Assange, the founder of WikiLeaks, of putting U.S. and Afghan lives at risk by releasing the documents to the media.
U.S. Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, and U.S. Defense Secretary Robert Gates condemned WikiLeaks for its actions.
"Mr. Assange can say whatever he likes about the greater good he thinks he and his source are doing, but the truth is they might already have on their hands the blood of some young soldier or that of an Afghan family," said Mullen.
Information contained in the field reports leaked to media reveals names of Afghan nationals who were working U.S. and international forces and accuses Pakistani intelligence officials of working with members of the Taliban.
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