United Airlines Flight 175

United Airlines Flight 175 was an American domestic passenger flight from Logan International Airport in Boston to Los Angeles International Airport in California that was hijacked by five al-Qaeda terrorists on the morning of September 11, 2001, as part of the September 11 attacks. The aircraft involved, a Boeing 767-200 carrying 51 passengers and 9 crew members (excluding the 5 hijackers), was deliberately crashed into the South Tower of the World Trade Center in New York City, killing everyone aboard and causing the deaths of more than 600 people in the South Tower's upper levels in addition to an unknown number of civilians and emergency personnel on floors beneath the impact zone.

Source: Wikipedia — United Airlines Flight 175 (CC BY-SA 4.0)