(NBC News) Federal agents and army investigators are searching for answers after a soldier opened fire at Fort Hood Wednesday, killing three and injuring 16 before turning his gun on himself.
"He walked into one of unit buildings opened fires got in vehicle fired from vehicle got out walked into other building and opened fire again," confirmed Lt. General Mark Milley.
The suspect has been identified by military sources as 34-year-old Army Specialist Ivan Lopez.
Lopez was undergoing diagnostic testing for post traumatic stress disorder prior to the shooting.
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