Fort Meade, Maryland (CNN) -- A convicted computer hacker from California testified Tuesday in Pfc. Bradley Manning's preliminary hearing about six days of chats he conducted with someone who claimed to have leaked classified information and was "looking to brag about what they had done." Adrian Lamo said he traded instant messages in a chat format with someone self-identified as Bradass87. Lamo testified that based on an e-mail he received from Manning, as well as an examination of Manning's Facebook page, that Bradass87 was Manning. The testimony came on the fifth day of the preliminary hearing, which will determine if Manning proceeds to a full military court-martial.
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Former hacker says he traded e-mails with someone he believes was Manning
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Witness says Manning punched her in the face
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Documents found on Manning's computers were seen later on WikiLeaks, investigator says
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The testimony came in a hearing to determine if Manning will face a court martial
She told of incidents of erratic behavior on the part of @placeholder that led her to report that she felt Manning shouldn't be handling classified information.