These plans for improvement were never realized. On the morning of September 11, 2001, Al-Qaeda-affiliated hijackers flew two Boeing 767 jets into the Twin Towers in a coordinated act of terrorism. At 8:46 a.m. Eastern Time (ET), a team of five hijackers intentionally crashed American Airlines Flight 11 into the northern facade of the North Tower. At 9:03 a.m. ET, a second team of five hijackers intentionally crashed United Airlines Flight 175 into the southern facade of the South Tower. After burning for 56 minutes, the South Tower collapsed at 9:59 a.m. At 10:28 a.m., the North Tower collapsed, after burning for 102 minutes. The attacks on the World Trade Center killed 2,753 people. The resulting collapse caused structural failure in many of the surrounding buildings as well, and the entire complex was soon destroyed.