A man mourns Saturday at the 9/11 Memorial in New York City on the 20th anniversary of the Sept. 11 attacks.
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Never Forget – Remembering 9/11 20 Years Later.
Former President Barack Obama (from left), former first lady Michelle Obama, President Biden, first lady Jill Biden and former New York City Mayor Michael Bloomberg attend 9/11 commemoration ceremony in New York City.
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U.S. service members attend the 9/11 observance ceremony at the National 9/11 Pentagon Memorial in Arlington, Va.
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An attendee puts her hand on the head of a child at the Flight 93 National Memorial in Shanksville.
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Bells are rung during a 9/11 commemoration at the Flight 93 National Memorial in Shanksville.
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Family members and loved ones of victims attend Saturday’s ceremony in New York City. Six moments of silence were held, marking when each of the World Trade Center towers was struck and fell, and the times corresponding to the attack on the Pentagon and the crash of Flight 93.
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A family member grieves at the National 9/11 Memorial and Museum ceremony commemorating the 20th anniversary of the 9/11 attacks on the World Trade Center, in New York City on Saturday.
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Investigators head into the debris field at the site of a commercial plane crash near Shanksville, Pennsylvania. REUTERS/Jason Cohn