Washington Navy Yard gunman had previous arrests and mental health issues, officials say

Map locates the Washington Navy Yard. / AP photo

Mondayâ??s deadly shooting at the Washington Navy Yard may raise more questions about the adequacy of the background checks that are done on government contract employees and others who are issued security clearances.

Officials say Aaron Alexis, an information technology employee with a defense contractor, used a valid pass to get into the Navy Yard building where he opened fire, killing 12 people.

Officials are also revealing that Alexis had been hearing voices and was being treated for mental problems in the weeks before the rampage. Still, he was able to keep his security clearance.

Officials say Alexis was given an early discharge from the Navy in 2011 because of insubordination and other problems, but the discharge was an honorable one.

Alexis had been arrested in connection with shootings in 2004 and 2010 in Texas and Seattle but wasn't charged.

The CEO of an IT-consulting company where Aaron Alexis once worked says the suspected gunman in the Washington Navy Yard massacre had "no personnel issues" he was aware of.

Thomas Hoshko of The Experts, a Florida-based company that contracts with the U.S. military, also says a background check of Alexis as recently as July revealed no criminal history.

Alexis was killed yesterday in a gun battle with police.

Law enforcement officials now say Alexis used a shotgun and two handguns in the assault -- but not an AR-15 assault rifle, as authorities had previously reported. An official says he arrived with the shotgun, and took the handguns away from law officers at the scene.