9/11 anniversary live updates: Memorial ceremonies planned at Ground Zero, Trump to visit Pentagon

America marks 25 years since the historic attacks. What to know: Ceremonies are planned in lower Manhattan, Washington, D.C., and Shanksville, Pa., to commemorate the 3,000 lives lost in the attacks on Sept. 11, 2001. This year's ceremony will include a moment of silence for those who have died of illnesses in the aftermath of the attacks. Today and NBC News will carry special coverage of the ceremonies throughout the day.

Follow live coverage of 9/11 memorial ceremonies 25 years later as Americans reflects on the attacks.