The 7 July 2005 Lonon bombings (also called the 7/7 bombings) were a series of coordinated bomb blasts planned by Islamist extremists that hit London's public transport system during the morning rush hour. At 8:50 a.m., three bombs exploded within fifty seconds of each other on three London Underground trains. A fourth bomb exploded on a bus nearly an hour later at 9:47 a.m. in Tavistock Square. The bombings killed 52 commuters and the four suicide bombers, injured 700, and caused disruption of the city's transport system (severely for the first day) and the country's mobile telecommunications infrastructure. The series of suicide-bomb explosions constituted the largest and deadliest terrorist attack on London in its history.