Whoever planted this device had no thought to the damage or injuries he may have caused

Deputy Assistant Commissioner Alan Fry

The latest blast comes just six weeks after a bomb, believed to have been planted by the same group, exploded outside BBC Television Centre in west London - at almost the same time on a Saturday night.

But unlike previous attacks thought to be linked to the Real IRA, police say that no coded warning was received before the Hendon device exploded.

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Speaking at the scene, Deputy Assistant Commissioner Alan Fry, head of Scotland Yard's anti-terrorist branch, said: "No threats were made. We suspect it was the work of the Real IRA.

The postal building suffered minor damage

"A high explosive device was placed outside the sorting office in a bricked-up former doorway."

The bomb was similar to that used in attack on Hammersmith Bridge in June last year, police maintain.

A Scotland Yard spokesman said: "We believe it contained between half and one pound of high explosives, which was a similar size to the device at Hammersmith Bridge in June last year."

A high grade bomb exploded underneath the bridge without warning in June 2000. No one was injured but the blast caused traffic chaos.

'Remain vigilant'

Deputy Prime Minister John Prescott described the Hendon blast as "worrying" and urged the public to remain vigilant.

"A number of incidents have taken place attributed to the Real IRA. That is worrying, of course, and intended to be worrying by the forces that are carrying out these terrorist activities," he told GMTV's Sunday programme.

Dissident attacks: London

June 2000: Hammersmith Bridge July 2000: Ealing Broadway Sept 2000: MI6 (Suspected, no warning given) Mar 2001: BBC Television Centre

Although no one was in the delivery depot at the time of the latest blast, Mr Fry said the building was near a pub and the busy Edgware Road.

"Whoever planted this device had no thought to the damage or injuries he may have caused," he added.

Mr Fry said the Edgware Road would probably be closed for the rest of Sunday.

A spokesman for Consignia, formerly the Post Office, said the building was a small delivery office dealing with mail for the NW9 area, and one of 100 similar-sized buildings in London.

BBC bomb

Police are still investigating the bomb which exploded outside BBC TV Centre in Wood Lane, White City, on 3 March.

The device - planted inside a taxi - detonated as bomb disposal experts attempted to carry out a controlled explosion on the vehicle.

The BBC bomb was also thought to have been the work of the Real IRA

One London Underground worker suffered minor injuries in the attack.

Warnings before the blast, issued to a London hospital and an unnamed charity, gave the same codeword as when a device was planted on the railway line at Acton, west London, last year.

At the time Mr Fry said he feared it was the escalation of a Real IRA terror campaign on mainland Britain.

Police have appealed for anyone who was in the area in the time leading up to the post office explosion or who may have seen something to contact the confidential Anti-Terrorist Hotline on 0800 789321.

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