The man responsible for Monday's deadly rampage at the Washington navy yard was a subcontractor and former reservist who was arrested at least twice in the past for gun-related offences. Aaron Alexis, 34, was discharged from the navy in 2011 after an incident in which an upstairs neighbour complained that he had shot into the floor of her apartment. But Alexis restored his connections with the navy when a professional services company subcontracted by Hewlett-Packard employed him on a navy IT project. His ID badge gained him access to the navy yard base on Monday, the FBI said.
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It was also reported that Alexis suffered post-traumatic stress brought on by the terror attacks of Sept. 11, 2001.