On February 26, 1993, Ramzi Yousef and associates carried out a van bomb terrorist attack below the North Tower of the World Trade Center in New York City. The 1,336-pound (606 kg) urea nitrate–hydrogen gas enhanced device was intended to make the North Tower collapse onto the South Tower, taking down both skyscrapers and killing tens of thousands of people. While it failed to do so, it was successful in killing six people, and caused over a thousand injuries. About 50,000 people were evacuated from the buildings that day.