The devices, described by George Churchill-Coleman, head of Scotand Yard's anti-terrorist branch as 'small and improvised', went off either side of a hoax bomb threat which closed down the capital's two busiest shopping streets and caused several hours of traffic chaos.
Last night, Flitcroft Street, near Charing Cross Road, was rocked by a bomb thought to have been placed behind a telephone junction box near Centre Point, one of London's most prominent landmarks and occupied by the Confederation of British Industry. First reports indicated that no one was injured, although the London Ambulance Service said that several people were treated for shock.
Witnesses said that the blast was felt several hundred yards away. Among those who felt the explosion was the actor David Jason, the star of the BBC's Only Fools and Horses. He said: 'I was in New Compton Street. (The explosion) was pretty heavy. I thought to myself 'I wonder if it's a bomb' because of the alerts today.' Chris Parker, 20, a student at the St Martin's School of Art in Charing Cross Road, said: 'I was working in a studio on the seventh floor and the whole building shook. We all evacuated the building and rushed out. The police quickly sealed off the area.'
The fire brigade said it was called in by police at 7.26pm. Scotland Yard said a search was made for a secondary device.
The first bomb exploded in a litter bin in Panton Street near Piccadilly Circus, at 1.45am, 35 minutes after a coded warning was telephoned to a London radio station. Scotland Yard said the caller failed to give a specific location and police teams were still searching the area when the device went off. Five people were slightly injured and taken to hospital but released after treatment. The bomb, believed to have been less than 2lb of Semtex, scattered fragments of the cast-iron litter bin for about 30 yards.
The Tory MP Peter Bottomley, a former Northern Ireland Minister, said: 'These bombs are designed for publicity during the Conservative Party conference.
'It is no coincidence that the second one . . .follows the conference speech by Sir Patrick Mayhew, Secretary of State for Northern Ireland, who has committed himself to search for a peaceful solution to the issues of the island of Ireland.'
In between the explosions, the two principal shopping streets in the West End of London were evacuated for more than two hours because of a bomb threat. Thousands of shoppers and store staff were cleared from Regent Street and Oxford Street following the warning just after 3pm. London Underground closed Marble Arch, Bond Street, Oxford Circus and Tottenham Court Road stations, causing further problems for travellers, although trains were allowed to pass through the stations.