Expert: Kemikaliemängd motsvarar Londonbomb

The 7 July 2005 London bombings, often referred to as 7/7, were a series of coordinated terrorist suicide attacks in London, United Kingdom, which targeted commuters travelling on the city's public transport system during the morning rush hour. Four radical Islamic terrorists separately detonated three homemade bombs in quick succession aboard London Underground trains across the city and, later, a fourth on a double-decker bus in Tavistock Square. The train bombings occurred on the Circle line near Aldgate and at Edgware Road, and on the Piccadilly line near Russell Square. Fifty-two people of 18 different nationalities, all of whom were UK residents, were killed, and more than 700 were injured, in the attacks, making it Britain's deadliest terrorist incident since the 1988 bombing of Pan Am Flight 103 near Lockerbie, Scotland, as well as the country's first Islamist suicide attack. The explosions were caused by triacetone triperoxide-based IEDs packed into backpacks. The bombings were followed two weeks later by a series of attempted attacks that failed to cause injury or damage. The 7 July attacks occurred the day after London had won its bid to host the 2012 Olympic Games.