Army Private First Class Bradley Manning pleaded guilty to 10 out of 22 charges at a military hearing at Fort Meade on Thursday in advance of his June 3 trial, according to the Washington Post.
The 25-year-old, who is charged with leaking classified material to WikiLeaks, said he believed the information "could spark a domestic debate as to the role of the military and foreign policy in general."
"I felt I accomplished something that would allow me to have a clear conscience," Manning said.
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The 10 charges carry a maximum penalty of 20 years in prison.
He is also faces charges including espionage and aiding the enemy, which he denies.
Last month military judge Colonel Denise Lind reduced Manning's sentence by 112 days for the harsh treatment he received at Quantico Marine Base in Virginia where he was placed in solitary confinement, Reuters reported.
WikiLeaks founder Julian Assange remains at the Ecuadorean Embassy in London where he took refuge in June to avoid extradition to Sweden.
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