Khalid Sheikh Mohammed (Alleged mastermind of 9/11)

Khalid Sheikh Mohammed is a Pakistani terrorist who is believed to have planned and coordinated the September 11, 2001, attacks in the United States. He is accused of devising the plot that involved hijacking airplanes and crashing them into the World Trade Center and Pentagon, causing nearly 3,000 deaths. He was captured in 2003 and has been held by U.S. authorities since. His role in the attacks makes him one of the most infamous terrorist figures, and he is seen as the key architect behind one of the deadliest terrorist acts in history.