The Mystery of the Fifth 9/11 Plane Unraveled

A United Airlines flight scheduled to take off from JFK Airport on September 11, 2001, could have been the fifth plane targeted by hijackers. Flight attendants and the pilot reported suspicious activity by four passengers in first class and two in business class. The plane was evacuated after the World Trade Center was hit, and two uniformed people were later seen running in the passenger cabin. The FBI interviewed the flight attendants and took them to a lineup to identify the passengers. TMZ will present the story of United 23 on Monday on FOX at 9 PM ET.