The U.S. is remembering the victims and heroes of 9/11, 23 years after terror attacks on the nation left nearly 3,000 dead on Sept. 11, 2001.

Ceremonies are taking place at the tragic sites of the attacks, including in New York City, from the Pentagon, and at the site of a plane crash in Pennsylvania.

An annual commemoration ceremony is underway at the 9/11 Memorial in NYC, the site of where the World Trade Center towers fell after each was struck by a hijacked plane and where the vast majority of lives were lost on that fateful day.

Family members there are reading the names of their lost loved ones.

Fresh off a presidential debate, Vice President Kamala Harris and former President Donald Trump put politics aside and shook hands at the ceremony. Also among them were President Joe Biden, vice presidential candidate JD Vance and Senate Majority Leader Chuck Schumer.

A ceremony is also taking place at the Pentagon, where members of the military will read the names of the 184 lives lost there.

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A ceremony in Shanksville, Pennsylvania, is honoring the 40 plane passengers and crew members who died at the crash site there. Because of their actions on Flight 93, an attack on the U.S. Capitol was thwarted.

During the ceremonies, six moments of silence are being observed, acknowledging when each of the Twin Towers was struck and fell, the times of the attack on the Pentagon, and the crash of Flight 93.

The tragic events of 9/11 were the worst terror attacks in history on American soil.

Out of the 2,753 people who lost their lives in the Sept. 11 attacks, approximately 40%, or 1,103 victims, still remain unidentified.

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