President Barack Obama, first lady Michelle Obama and White House staffers observed a moment of silence Tuesday on the White House south lawn in memory of the Sept. 11, 2001, terrorist attacks.
With three bell tolls and a bugler playing taps, the White House observance marks the 11th anniversary of the suicide hijackings that struck New York and the Pentagon and downed a plane in Pennsylvania, leaving nearly 3,000 dead.
Obama and the first lady also planned to attend an observance ceremony at the Pentagon later Tuesday morning.
In the afternoon, the president was scheduled to visit wounded soldiers and their families at Walter Reed National Military Medical Center.
Vice President Joe Biden was traveling to Pennsylvania to deliver remarks at the Flight 93 National Memorial Commemorative Service.
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