Incident Summary:

09/11/2001: This was one of four related attacks that occurred in the United States that are known collectively as the 9/11 Attacks. In the second of these attacks, which occurred at 9:03 a.m. local time, United Airlines Flight 175 crashed into the South Tower of the World Trade Center Complex in New York City, New York. Five hijackers belonging to Al-Qaida hijacked the Boeing 767 aircraft on a flight originating from Logan International Airport in Boston, Massachusetts, and destined for Los Angeles International Airport. There were 56 passengers, nine crew members and five hijackers on the plane, all of whom died upon impact. The South Tower collapsed at 9:59 a.m. local time, killing all who were trapped inside or located nearby. The North Tower collapsed, after having been struck by American Airlines Flight 11, at 10:28 a.m. local time. At least 2,770 people died as a result of the attacks in New York City, including 10 hijackers as well as responders who contracted cancer and respiratory illnesses at the attack site and passed away years later. More than 21,000 others were injured, according to information reported by the September 11th Victims Compensation Fund. Al-Qaida leaders including Osama bin Laden and Khalid Shaikh Mohammed claimed responsibility for the attacks in multiple videotaped interviews.



United States

North America

region/u.s. state:

New York

New York City

Attack Information
Type of Attack (more) Armed Assault
Type of Attack (more) Hijacking
Successful Attack? (more) Yes
Target Information (more)
Target Type: Airports and Aircraft
Name of Entity United Airlines
Specific Description United Airlines-owned Boeing 767 passenger jet aircraft
Nationality of Target United States
Target Type: Business
Name of Entity World Trade Center Complex
Specific Description Businesses operating inside the Twin Towers
Nationality of Target United States
Target Type: Private Citizens & Property
Name of Entity Civilians
Specific Description Passengers and crew members on United Airlines Flight 175 and the people working in the South Tower of the World Trade Center in New York City
Nationality of Target Multinational
Additional Information
Hostages Yes
Number of Hostages 59
US Hostages 54
Hours of Kidnapping 1
Outcome Hostage(s) killed (not during rescue attempt)
Ransom No
Property Damage Yes
Extent of Property Damage Catastrophic (likely > $1 billion)
Value of Property Damage Unknown
Weapon Information
Type Sub-type
Vehicle (not to include vehicle-borne explosives, i.e., car or truck bombs)
Incendiary Gasoline or Alcohol
Melee Knife or Other Sharp Object
Weapon Details
The attackers reportedly gained control of the plane using sharp objects resembling knives or other sharpened metal objects. The attackers turned the airplane into a missile when flying it into the South Tower of the World Trade Center Complex. The airplane's jet fuel ignited the building and resulted in a massive fire that contributed to the collapse of the South Tower. Mace may have also been used in subduing the passengers and crew members.
Additional Information
Suicide Attack?Yes
Part of Multiple Incident?Yes
Criterion 1 (more) Yes
Criterion 2 (more) Yes
Criterion 3 (more) Yes
Doubt Terrorism Proper (more) No
Additional Information This attack was one of four related incidents (cf. 200109110004-07). Flight attendant, Robert Fangman, called a United Airlines office in San Francisco and spoke with Marc Policastro. He reported the hijacking and said that both pilots had been killed. He also reported that a flight attendant was stabbed and said that the hijackers were flying the plane. United Flight 175 departed from Boston's Logan International Airport at 8:14 am local time. At 8:47 am, air traffic control received the first indications that the plane was hijacked. Since the airplane impacted the South Tower at 9:03 am, the length of the hijacking was at least 16 minutes. The second aircraft seized was United Airlines flight 175, which was scheduled to depart from Logan at 8:00 and fly directly to Los Angeles. Details on the number of people wounded in the attacks are very difficult to confirm The numbers reported in the GTD are conservative estimates for immediate casualties, first responders, and residents, based on documentation for the September 11th Victims Compensation Fund (VCF).
Perpetrator Group Information
Group Name Claimed Responsibility
Al-Qaida Yes (Confirmed: Unknown; Mode: Video)
Perpetrator Statistics
Number of Perpetrators 5
Number of Captured Perpetrators 0
Casualty Information
Total Number of Casualties 1385 Fatalities / 10878 Injured
Total Number of Fatalities 1385
Number of U.S. Fatalities 1327
Number of Perpetrator Fatalities 5
Total Number of Injured 10878
Number of U.S. Injured Unknown
Number of Perpetrators Injured 0
United States Government, The 9/11 Commission Report: Final Report of the National Commission on Terrorist Attacks Upon the United States. Washington, DC: Government Printing Office, 2004.
Lindsay Kines, “United States on high alert after thousands feared dead: Airlines initially blame hijackers for attacks on the Pentagon in Washington, New York's World Trade Center,” The Vancouver Sun, September 11, 2001.
Joe Frolick, “Hijackers Ram Two Airliners Into World Trade Center, Third Plane Slams Into Pentagon, Fourth Crashes Near Pittsburgh; Thousands Die; Bush Vows Swift Revenge,” The Plain Dealer, September 12, 2001.