How many died in 9/11? A look at the tragic attack 23 years ago

This Sept. 11 marks 23 years since the terrorist attack on the World Trade Center and the Pentagon, an event that respondents increasingly say impacted American lives forever, a USA TODAY/Suffolk University poll found.

On the morning of Sept. 11, United Airlines Flight 175 and American Airlines Flight 11 departed from Boston en route to California before hijackers crashed them into the North and South towers of the World Trade Center in New York City. American Airlines Flight 77 hit the Pentagon, while passengers attempted to overtake United Airlines Flight 93 from hijackers before it crashed in a field in Pennsylvania.

A woman runs at sunrise in the Empty Sky 9/11 Memorial in Liberty State Park  in Jersey City, New Jersey on September 11, 2021.
A woman runs at sunrise in the Empty Sky 9/11 Memorial in Liberty State Park in Jersey City, New Jersey on September 11, 2021.

How many people died in 9/11?

The 9/11 attacks left 2,977 dead across New York, Washington, D.C. and Pennsylvania, according to the 9/11 Memorial and Museum. That total includes the 2,753 who died in New York, 184 people at the Pentagon and 40 people who died when Flight 93 crashed in Pennsylvania.

The youngest flight passenger who died was Christine Hanson, a 2-year-old on her way to Disneyland on United Airlines Flight 175. The oldest was Robert Norton, 82, on American Airlines Flight 11.

The 19 hijackers from the militant Islamic extremist group al-Qaeda also died.

The 9/11 victims are memorialized at the site of the former World Trade Center towers. The victims’ names are engraved around pools based on their location at the time of the attacks and their relationship to other victims, so “almost every name is surrounded by people they cared about in some way,” according to the 9/11 Ground Zero Tour. Each morning, staff members place white roses on certain names to signify the victim’s birthday.

A rose and a photograph are placed on one of the victims' names at the north reflecting pool of the National 9/11 Memorial, two days before the 19th anniversary of attacks, in the lower section of Manhattan, New York City, U.S. September 9, 2020.
A rose and a photograph are placed on one of the victims' names at the north reflecting pool of the National 9/11 Memorial, two days before the 19th anniversary of attacks, in the lower section of Manhattan, New York City, U.S. September 9, 2020.

Sept. 11 by the numbers: Facts from a tragic day in American history

How many firefighters died on 9/11?

Three hundred and forty-three firefighters died on 9/11, which at the time was nearly half the number of on-duty deaths in the New York City Fire Department’s entire 100-year history.

In 2019, it was reported that the 200th New York City firefighter had died from Ground Zero-related illnesses, including the effects of toxic contaminants, traumatic injuries and physical and emotional stress. In 2022, the FDNY reported that number was closer to 300.

According to the World Trade Center Health Program, close to 80,000 individuals have been diagnosed with physical and mental health conditions brought on by exposure to the dust, smoke, debris and trauma of the 9/11 attacks.

How many 9/11 victims were never found?

Around 40% of the victims have yet to be identified, according to the New York City Office of Chief Medical Examiner (OCME). That’s about 1,103 people. In January, OCME identified the 1,650th victim using advanced DNA analysis – John Ballantine Niven, 44, of Oyster Bay, New York, was a senior vice president at Aon Risk Services

The effort to identify World Trade Center victims is the “largest and most complex forensic investigation in the history of the United States,” OCME reports.

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This article originally appeared on USA TODAY: How many people died in 9/11? Terrorist attack by the numbers.