On the morning of Tuesday, September 11, 2001, hijackers crashed American Airlines Flight 11 into the North Tower of the World Trade Center in New York City at 8:46 a.m., and in the series of attacks that followed, United Airlines Flight 175 struck the South Tower, American Airlines Flight 77 crashed into the Pentagon in Arlington, Virginia, and passengers aboard United Airlines Flight 93 thwarted a fourth attack, causing that aircraft to crash near Shanksville, Pennsylvania. In total, 2,977 people died in the deadliest terrorist attack in the nation's history. The attacks transformed the Federal Bureau of Investigation, strengthening its role in collaboration and information sharing to detect and deter terrorism and crime, while it remained dedicated to protecting the American people and upholding the Constitution of the United States. A memorial site reflects the New York City blocks that housed the World Trade Center complex, with physical elements representing buildings directly or collaterally involved in the attacks and their levels of damage, including a 22-foot-tall steel box column from the wreckage marking the North Tower, a 6-foot-tall granite monolith marking the South Tower, concrete benches for Trade Center buildings that collapsed, and distinctive landscaping for collaterally damaged buildings.