Bradley Manning, the 22 year old US army intelligence analyst, leading suspect in the leaking of thousands of US military documents to WikiLeaks had been disciplined at least twice since 2007 but managed to maintain his security clearance, a media report said on Tuesday.
Manning already was facing military charges for allegedly leaking a 2007 Iraq battle video to the WikiLeaks website and for downloading sensitive documents.
Now, according to US military sources, he is the lead suspect in the investigation into the leaked documents, considered to be the biggest leak in US military history of classified documents on the war in Afghanistan.
But the recent incidents are not his first brushes with problems in the Army. During his training to become an intelligence analyst, Manning was reprimanded by commanders at Fort Huachuca, Arizona, CNN reported.
"Manning, during advanced individual training, broke the rules and received a non-judicial punishment," it quoted Tanja Linton, a Fort Huachuca spokeswoman as saying.
She did not elaborate on how he broke the rules. Wired.com recently reported that he was punished for uploading videos on YouTube in which he talked about classified buildings at the base and classified materials he saw.
Manning did not disclose classified information in the videos, but did discuss the rooms where secure information was held, which was considered a security risk, Wired.com reported.
Despite the punishment, Manning graduated from his training in August 2008 as an intelligence analyst with security clearance.
But just a couple of months before Manning was arrested in Iraq, he was disciplined again, CNN quoted a military official as saying.
Manning had got into a fight with another service member, according to the military official, although the circumstances are unclear. As a result, Manning was demoted a stripe, from specialist to private first class.
Manning had "top secret" and "sensitive compartmentalised information" clearance, according to a military official. Top secret is a lower level of clearance, but SCI level information is on a "need to know" basis and codes may be required to gain access to it.
Manning continues to be held in solitary confinement at the Quantico Marine base in Virginia. He is accused of leaking classified information to the WikiLeaks website, including the video of a deadly US helicopter attack in Iraq.