A wreath is left after a ceremony by military leaders, to honor the victims of the attack at the Navy Yard, at the Navy Memorial in Washington, September 17, 2013. Washington authorities questioned on... more 
A wreath is left after a ceremony by military leaders, to honor the victims of the attack at the Navy Yard, at the Navy Memorial in Washington, September 17, 2013. Washington authorities questioned on Tuesday how a U.S. military veteran with a history of violence and mental problems could have gotten clearance to enter a Navy base where he killed 12 people before police shot him dead. The suspect, Aaron Alexis, 34, a Navy contractor from Fort Worth, Texas, entered Washington Navy Yard on Monday morning and opened fire, spreading panic at the base just a mile and a half (2.5 km) from the U.S. Capitol and three miles (4.8 km) from the White House. REUTERS/Mike Theiler (UNITED STATES - Tags: MILITARY CIVIL UNREST CRIME LAW OBITUARY) less 
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Reuters | Photo By MIKE THEILER / REUTERS
Tue, Sep 17, 2013 11:25 AM EDT