The gunman who killed 12 people at the Navy Yard in Washington, D.C. on Monday served in the Navy beginning in 2007, before being dismissed from the service in 2011 because of a variety of misconduct issues.
After his rampage yesterday, Aaron Alexis was shot and killed. The FBI is now attempting to learn everything they can about his past.
"No piece of information is too small," authorities said at a news conference.
After joining the Navy in 2007, Alexis, 34, became a sailor in 2009. According to multiple reports, he was an aviation electrician.
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Originally from Queens, N.Y., his last known residence was in Fort Worth, Texas. The members of his immediate family all live in Brooklyn, N.Y., ABC News reported.
Authorities do not have a motive for the shootings at this time. Sources indicate Alexis was armed with three weapons: an assault rifle, a shotgun and a pistol. The three guns were all recovered in close proximity to his body.
Alexis worked for Hewlett-Packard as an IT subcontractor for the Navy. It's unclear if he actually worked at the Navy Yard itself.
"We are deeply saddened by today's tragic events at the Washington Navy Yard," an HP spokesperson said in a statement. "HP is cooperating fully with law enforcement as requested."
It's being reported that Alexis was involved in previous shooting incidents in Seattle and Fort Worth. After Alexis shot out another man's tires during "an anger-fueled 'blackout'" in Seattle, a detective spoke with his father.
"Mr. Alexis then told me that his son had experienced anger management problems that the family believed was associated with PTSD," the detective wrote in a report. "He confirmed that his son was an active participant in rescue attempts of September 11th, 2001."
The FBI is asking that anyone with information on Alexis call 1-800-CALL-FBI.
In addition to the dead, at least 12 people were wounded at the Navy Sea Systems Command headquarters.
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