BBC bomb linked to three others
The bomb which exploded outside BBC Television Centre is being linked with three previous attacks believed to be the work of the Real IRA.
A coded warning was received by a London hospital at 11.22pm on Saturday saying a maroon London taxi containing a bomb was parked outside BBC.
A second coded warning was issued to an unnamed charity at 11.24pm.
The taxi, parked near a bus stop outside the main entrance to the Television Centre, was destroyed in the blast and debris scattered over a 150-metre area.
On June 1 last year a bomb exploded under Hammersmith Bridge at 4.30am, while on July 19 police performed a controlled explosion on a device found alongside railway lines in Acton, west London.
On September 20 a rocket launcher was fired at the MI6 headquarters in Vauxhall Cross, south east London.
The head of the Metropolitan Police Anti-Terrorist Branch, Deputy Assistant Commissioner Alan Fry, is appealing for the public to be vigilant and for information on the attack.
He said: "I urge everyone to be vigilant. Many times we have seen communities defeat terrorism and through them we can get to those responsible for this evil deed.
"Once again we see that coded warnings have put the public at risk - it has proved good fortune that there were no serious casualties on this occasion."
Mr Fry is appealing for anyone with information to call the Anti-Terrorist Hotline on 0800 789321.
