Bells tolled across New York City and moments of silence were being observed across the nation Wednesday as America commemorates the 18th anniversary of the Sept. 11 terror attacks.

A moment of silence was observed at 8:46 a.m. ET to mark the time the first plane hit – American Airlines Flight 11, flying from Boston to Los Angeles, had been hijacked before slamming into the north face of the North Tower.

President Donald Trump joined a moment of silence on the South Lawn of the White House, with hundreds of guests that included 9/11 survivors and family members and current and former law enforcement personnel.

In New York, the names of the almost 3,000 victims were being solemnly read at the National September 11 Memorial & Museum. Intermittent moments of silence marked the impact times for the second Ground Zero plane, the moments when each tower collapsed, and the impact times for the planes that struck the Pentagon and a field in Shanksville, Pennsylvania.

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At 9:03 a.m., United Airlines Flight 175, also bound for Los Angeles from Boston, crashed into the south face of the World Trade Center’s South Tower. At 9:37 a.m., American Airlines Flight 77, scheduled to fly from Washington to Los Angeles, hit the Pentagon.

At 10:03, Flight 93, flying from Newark, N.J., to San Francisco, slammed into a field in Pennsylvania after some of the passengers fought hijackers who had been trying to hit a target in Washington, D.C.

The World Trade Center’s South Tower collapsed at 9:59 a.m.; the North Tower fell 29 minutes later.

The New York ceremony was open only to family members of victims, but the event was being streamed live. The memorial will open to the public later in the day.

In Shanksville, the observance began at 9:45 a.m. at the Flight 93 Memorial Plaza. At 10:03 a.m. – the moment Flight 93 crashed – the names of the 44 passengers and crew members will be read and the Bells of Remembrance will be rung in their memory. A wreath will then be placed at the Wall of Names at the site.

At the Pentagon Memorial, survivors and families of the 184 people who died there were marking the anniversary in a private ceremony from 9:30-11 a.m. Trump was scheduled deliver remarks. The public can visit the memorial after the ceremony is concluded.

Contributing: David Jackson

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