The US State Department has detailed a number of "extraordinary steps" taken to limit international fallout after thousands of classified documents were published on WikiLeaks.
The former army intelligence analyst faces a total of 22 charges - including aiding the enemy - after thousands of classified documents allegedly downloaded by the soldier ended up on the whistle-blowing website.
According to the State Department testimony obtained by the Associated Press, one group of up to 25 high-ranking officials worked around the clock in an attempt to limit damage before the documents went live.
A second group tried to identify individuals around the world who might be put at risk, while a third group focused on improving cyber security. At least several hundred people were identified as being at risk, with a few ultimately being moved to safer locations.
The State Department also authored a letter released just hours before the WikiLeaks documents were published, warning the material would "place at risk the lives of countless innocent individuals" and threaten numerous military operations as well as international cooperation.
"I would think we would continue to see reporting of damage from WikiLeaks conceivably for many years to come," said State Department witness, Deputy Assistant Secretary Catherine Brown.
Manning's military trial is slated to begin on September 21. If found guilty, the former army intelligence analyst will likely spend the rest of his life in the brig without the chance of parole.