Among the more indelible images to emerge from the terrorist attacks on September 11 are the photographs and video footage of two airplanes flying into the North and South Towers of the World Trade Center in lower Manhattan. At 8:46 a.m. on the morning of September 11, 2001, five hijackers crashed American Airlines Flight 11 into floors 93 through 99 of the North Tower. Seventeen minutes later, United Airlines Flight 175 was crashed into floors 77 through 85 of the South Tower. Both buildings would ultimately collapse, killing untold numbers of innocent people. The attack on 9/11 was the second terrorist attack on the World Trade Center in less than a decade. On February 26, 1993, approximately 1,200 pounds of explosives in a rental van parked in the underground parking garage of the World Trade Center was detonated by a small cell of terrorists linked to a local radical mosque and an Islamist terror network. The 9/11 Memorial & Museum notes that the explosion created a five-story, 150-feet-wide crater. The attack injured more than 1,000 people and killed six, including Monica Rodriguez Smith, who was pregnant. The day of the attack was her last day of work before maternity leave. Two memorials, a fountain and a brass plaque bearing the names of the victims of the 1993 attack, were ultimately created to commemorate those who lost their lives. Each memorial was destroyed in the attacks on September 11, 2001, but a small piece of the fountain was recovered in the aftermath of 9/11. That piece was rededicated on February 26, 2005.