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A view over New York City and the 'Tribute In Light' marking the twelfth anniversary of the terrorist attacks at the World Trade Center, on Sept. 11, 2013 in New York City. New York City and the rest of the nation are commemorating the twelfth anniversary of the Sept. 11, 2001 attacks which resulted in the deaths of nearly 3,000 people after two hijacked planes crashed into the World Trade Center, one into the Pentagon in Arlington, Va., and one crash landed in Shanksville, Pa.
By Sophia Rosenbaum and Matthew DeLuca, NBC News
At memorials and in their schools, homes, and places of work across the country on Wednesday morning, Americans paused to remember those lost in the Sept. 11 attacks that shook the nation 12 years ago.
At 8:46 a.m. EST, crowds gathered at the site of the Twin Towers in New York City observed a moment of silence marking when the first plane crashed in the city’s downtown. President Barack Obama joined by the Vice President and First Lady also marked the moment on the lawn of the White House.
The president later observed a moment of silence at the Pentagon to mark the time at which Flight 77 struck the building, joined by Secretary of Defense Chuck Hagel and Joint Chiefs of Staff Chairman Gen. Martin Dempsey.
“Let us have the strength to face down the threats that endure, different though they may be from 12 years ago, so that as long as there are those who will strike our citizens, we will stand vigilant and defend our nation,” the president said outside the Pentagon.
Justin Lane / Pool via EPA
Ceremonies at the World Trade Center, the Pentagon, and Shanksville, Pa., mark 12 years since the attacks.