In the series by Newsweek, the events leading to September 11, 2001, are explored daily as they unfolded 20 years ago. An advisory from the intelligence office of the Federal Aviation Administration (FAA) on August 16, labeled ‘Disguised Weapons,’ prompted a warning to airlines. It indicated the possibility of terrorists using modified everyday items to hijack aircraft.
Despite this warning, airport security remained largely unchanged. The 9/11 attackers used knives and razors, items that were legally allowed on planes at the time. Evidence from phone calls made by flight attendants and passengers during the attacks revealed that those who resisted in First Class were injured by attackers wielding these weapons.
In December 1999, Khalid Sheikh Mohammed began testing the security of bringing knives and razor blades, known as box cutters, onto flights. He first experimented when Walid bin Attash, nicknamed ‘Khallad,’ carried a razor knife on a flight from Pakistan to Malaysia for reconnaissance. Khallad, a close associate of Mohammed, further probed airline security by bringing knives on flights to Malaysia, Bangkok, and Hong Kong. In January 2000, while accompanying Khalid al-Mihdhar and Nawaf al-Hazmi to Malaysia, he again carried a knife onboard.
Khallad shared his insights with Mohammed and Mohammed Atta. When Atta returned to the U.S. from Zurich on July 8, after meeting Ramzi Bin al-Shibh in Spain, he carried two Victorinox Swiss Army knives bought at Zurich airport onboard.
After the attacks, the Federal Bureau of Investigation (FBI) painstakingly examined financial records and concluded that terrorists on every hijacked flight had bought at least seven knives. On August 13, Marwan al-Shehhi, the pilot of UA Flight 175 that struck the South Tower, purchased two knives at a Sports Authority in Boynton Beach, Florida. Two associates, Fayez Banihammad and Hamza al Ghamdi, bought additional blades at a local Wal-Mart.
Later that month, on August 27, Nawaf al-Hazmi, involved in AA Flight 77 that hit the Pentagon, bought a multi-tool knife at a Target store in Maryland. While no purchases were linked to the hijackers on UA Flight 93, which crashed in Pennsylvania, the FBI found 14 knives, including a box cutter, among the debris, with none exceeding 3.5 inches in blade length.
Ramzi Bin al-Shibh, apprehended post-9/11, informed interrogators about their strategy discussions in Spain. He explained that Atta, al-Shehhi, and Ziad Jarrah faced no issues carrying box cutters on domestic flights during the planning stage.
As Newsweek continues to unfold these events, they offer a live tweet on September 11 starting at 4:45 a.m. EST. Each day offers a detailed recount of the build-up to the tragic events of 9/11.