9/11: What happened and how many people died in September 11 attacks?

September 10, 2026

On September 11, 2001, members of the terrorist organization al-Qaeda hijacked four commercial aircraft over the eastern United States and deliberately crashed them into major landmarks. Two planes struck the Twin Towers of the World Trade Center in New York City, causing both structures to collapse within two hours, while a third plane hit the Pentagon near Washington, D.C., and a fourth crashed in Pennsylvania after passengers resisted the hijackers. The coordinated attacks resulted in 2,977 deaths, with citizens from 77 countries among the victims, and triggered a U.S.-led invasion of Afghanistan less than a month later.

Who is affected

2,977 victims who died in the attacks (not including the 19 hijackers)
246 passengers and crew aboard the four planes
2,606 people at the Twin Towers
125 people at the Pentagon
441 New York City first responders who died
An estimated 17,400 people who were in the Twin Towers when the first plane struck
Thousands of people injured or who developed illnesses connected to the attacks
Citizens from 77 different countries
Firefighters who worked in toxic debris
People who developed health problems linked to dust and smoke (claiming more than threefold the number of lives lost in the attacks)

What action is being taken

A series of events will take place on Friday in the United States to mark the 25th anniversary of the 9/11 attacks
A military court at Guantanamo Bay has been considering whether and how Khalid Sheikh Mohammed can be tried for his role in 9/11

Why it matters

The 9/11 attacks had profound consequences across the globe, triggering fundamental changes in U.S. foreign policy and international security measures. The attacks led to nearly 20 years of U.S. military involvement in Afghanistan, the longest war in American history, and reshaped counterterrorism efforts worldwide. The ongoing health crisis stemming from the attacks continues to claim lives even decades later, with deaths from related illnesses now exceeding threefold the original death toll. The attacks also raised complex legal and ethical questions about detainee treatment and justice that remain unresolved more than two decades later, as evidenced by the ongoing proceedings against the alleged mastermind at Guantanamo Bay.

What's next

No explicit next steps stated in the article

Read full article from source: BBC