At approximately 8.50am on 7 July 2005, three near-simultaneous explosions rocked the central London underground railway system. The first occurred in a Circle Line tunnel between Liverpool Street and Aldgate stations, the second on the Circle Line just outside Edgware Road and the third in a Piccadilly Line tunnel between King's Cross and Russell Square. At 9.47 am, a fourth explosion occurred on the upper deck of a number 30 bus in Tavistock Square.

In total, 52 members of the public and four suicide bombers died in the attacks, and over 700 people were injured. Among these were one Australian killed and 11 injured. The London Ambulance Service treated over 400 patients, some with horrific injuries, with support from St John Ambulance, the Red Cross, and surrounding ambulance services. Following the attacks, the Commonwealth Government announced a package of assistance and support for Australians affected by the bombings.

The tunnel environment presented a challenge to emergency services personnel in the rescue efforts, limiting communication capacity.