London bombings

The 7 July 2005 London bombings (often referred to as 7/7) were a series of co-ordinated suicide attacks in London which targeted civilians using the public transport system during the morning rush hour.

On the morning of Thursday, 7 July 2005, four Islamist home-grown terrorists detonated four bombs, three in quick succession aboard London Underground trains across the city and, later, a fourth on a double-decker bus in Tavistock Square. Fifty-two civilians and the four bombers were killed in the attacks, and over 700 more were injured.

The explosions were caused by homemade organic peroxide-based devices packed into rucksacks. The bombings were followed exactly two weeks later by a series of attempted attacks.

London Underground

Further information: Timeline of the 2005 London bombings

See also: Attacks on the London Underground

At 8:50 am, three bombs were detonated on board London Underground trains within fifty seconds of each other:

The first exploded on a Circle line sub-surface train, number 204, travelling eastbound between Liverpool Street and Aldgate. The train had left King's Cross-St. Pancras about eight minutes earlier. At the time of the explosion, the third carriage of the train was approximately 100 yards (90 m) along the tunnel from Liverpool Street. The parallel track of the Hammersmith and City line between Liverpool Street and Aldgate East was also damaged in the blast.

The second device exploded in the second carriage of another Circle line sub-surface train, number 216, which had just left platform 4 at Edgware Road and was travelling westbound toward Paddington. The train had also left King's Cross-St. Pancras about eight minutes previously. There were several other trains nearby at the time of the explosion; an eastbound Circle line train (arriving at platform 3 at Edgware Road from Paddington) was passing next to the bombed train and was damaged, along with a wall that later collapsed. There were two other trains at Edgware Road: an unidentified train on platform 2, and a southbound Hammersmith & City line service that had just arrived at platform 1.

A third bomb was detonated on a Piccadilly line deep-level Underground train, number 311, travelling southbound from King's Cross-St. Pancras and Russell Square. The device exploded approximately one minute after the service departed King's Cross, by which time it had travelled about 500 yards (450 m). The explosion occurred at the rear of the first carriage of the train, in car number 166, causing severe damage to the rear of that carriage as well as the front of the second one. The surrounding tunnel also sustained damage.

It was originally thought that there had been six, rather than three, explosions on the Underground network. The bus bombing brought the reported total to seven; this was clarified later in the day. The erroneous reporting can be attributed to the fact that the blasts occurred on trains that were between stations, causing wounded passengers to emerge from both stations, giving the impression that there was an incident at each. Police also revised the timings of the tube blasts: initial reports had indicated that they occurred during a period of almost half-an-hour. This was due to initial confusion at London Underground (LU), where the explosions were initially believed to have been caused by power surges. One initial report, in the minutes after the explosions, involved a person under a train, while another described a derailment (both of which did occur, but only as a result of the explosions). A code amber alert was declared by LU at 09:19, and LU began to cease the network's operations, ordering trains to continue only to the next station and suspending all services.

The effects of the bombs are understood to have varied due to the differing characteristics of the tunnels in which they occurred:

The Circle line is a "cut and cover" sub-surface tunnel, about 7 m (21 ft) deep. As the tunnel contains two parallel tracks, it is relatively wide. The two explosions on the Circle line were probably able to vent their force into the tunnel, reducing their destructive force.

The Piccadilly line is a deep-level tunnel, up to 30 m (100 ft) below the surface and with narrow (3.56 m, or 11 ft 8¼ in) single-track tubes and just 15 cm (6 in) clearances. This confined space reflected the blast force, concentrating its effect.

Claims of responsibility

Even before the identity of the bombers became known, former Metropolitan Police commissioner Lord Stevens said he believed they were almost certainly born or based in Britain, and would not "fit the caricature al-Qaeda fanatic from some backward village in Algeria or Afghanistan". The attacks would have required extensive preparation and prior reconnaissance efforts, and a familiarity with bomb-making and the London transport network as well as access to significant amounts of bomb-making equipment and chemicals.

Some newspaper editorials in Iran blamed the bombing on British or American authorities seeking to further justify the War on Terror, and claimed that the plan that included the bombings also involved increasing harassment of Muslims in Europe.