Vincent Ward said Friday that Manning attempted suicide last month at the military prison at Fort Leavenworth, though the attorney declined to divulge specifics. Manning also tried to take her own life in July.
Wayne Hall, an Army spokesman, on Friday would not discuss the latest attempt, citing medical privacy laws.
Manning is serving a 35-year sentence. She was arrested in 2010 as Bradley Manning and was convicted in 2013 in military court of leaking more than 700,000 secret military and State Department documents to WikiLeaks.
Manning was an intelligence analyst in Iraq at the time.
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