A controlled explosion was carried out on the car, packed with 60 litres of petrol, gas cylinders and nails, in Haymarket, near Piccadilly Circus. An ambulance crew saw smoke coming from the green Mercedes, near the Tiger Tiger nightclub at 0130 BST (0030 GMT). London's Park Lane was later cordoned off while a suspicious vehicle was investigated.
Scotland Yard, Assistant Commissioner Tarique Ghaffur urged people to be "alert and vigilant" and to report any suspicions to the police. Disruption would be kept to a minimum, he said, although the police were reviewing the safety of a number of big public events set to take place in the capital over the weekend. "I want to reassure Londoners that we are doing everything possible to make them safe," he added. Earlier, a Scotland Yard spokeswoman said that Park Lane was closed at Marble Arch to Hyde Park Corner and a 200m cordon was in place.
Sources close to the investigation said the Park Lane closure was linked to the discovery of a vehicle at an underground car park. A police robot was being used to investigate the vehicle. "International elements" were believed to be involved with the Haymarket bomb. It is suspected that this is the work of an Islamic extremist group, due to the construction of the bomb being very similar to the make of insurgents in Iraq and Afghanistan. The nails were a very popular method by the now 'disbanded' IRA, however it is unlikely.