(NBC News) Three victims remain in critical condition in the wake of Wednesday's shooting at Fort Hood.
The alleged gunman has been identified as Ivan Lopez, an Iraq War veteran being treated for mental illness.
"He was undergoing a variety of treatment and diagnoses for mental health conditions," Army Secretary John McHugh confirmed Thursday.
Army officials say he saw no combat while serving in Iraq and had showed no signs of violence when examined by a psychiatrist last month.
Investigators are pouring over his background in an effort to determine a motive.
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