The bomb - which contained up to 40kg of homemade explosive - blew up near Ealing Broadway railway station seconds after midnight.

The area - which is lined with bars and restaurants - was still busy with late night drinkers as the car exploded, sending up a sheet of flame and smashing numerous shop windows in a 200m radius.

Click here to see a map of the blast area

It blew up minutes before 150 people were about to leave a karaoke night at the nearest pub.

The attack, suspected to be the work of the Real IRA, comes at an extremely sensitive time in the Northern Ireland peace process.

The group has stepped up its campaign at a time when the parties are considering whether to accept a political package from the British and Irish governments.

On Wednesday a 20kg car bomb was defused at Belfast International Airport.

A threatening phone call was made at 2333 BST on Thursday to an on-call doctor service and the device exploded as police were searching for the vehicle, he said.

'Barbaric act'

The car, a grey Saab 9000 turbo five door with the registration E304 HPY, is thought to have been placed at around 2300BST.

"We are fortunate indeed that we are not dealing with mass murder," Mr Fry said, describing the planting of the bomb as a "barbaric act".

Mr Fry was unable to confirm whether the timing of the bomb was linked directly to the peace process or even the Queen Mother's 101st birthday.

"We know this is a difficult time as far as the peace process is concerned and as such perhaps we were more likely to see an attack at this time by a group who are determined to derail the peace process."

Non-existent road

Addressing speculation that the bomb might have been placed to coincide with the Queen Mother's birthday on Saturday, he said: "We hope not.

"But we are dealing with people who do not necessarily think in the same way as we do and with something we would wish to celebrate perhaps their intentions are something different."

London Mayor Ken Livingstone warned people to be "extra vigilant" over summer.

"The fact that the terrorists gave the police misinformation clearly shows their total disregard for members of the public."

Mr Fry said police were told the bomb was in Ealing Broadway Road, which does not exist, and no time of detonation was given.

A spokesman for the hospital said no-one had life-threatening injuries but two could be kept in over the weekend.

Mr Fry said the bomb was about twice the size of a taxi bomb - blamed on the Real IRA - that detonated outside BBC Television Centre in March.

"This was a calculated evil act by people who are seeking to maim and kill," Mr Fry added.

The area around Ealing Broadway shopping centre was also hit by flooding after the blast, with a burst pipe leaving up to two feet of water gushing through the streets.

Group blamed

The Real IRA first came to international prominence in August 1998 with the Omagh bomb which killed 29 people and wounded 200 others.

Since then, the group has been blamed for a series of explosions in Northern Ireland and in mainland Britain.

These included a rocket-propelled grenade attack on the London headquarters of MI6 in September 2000, and a taxi bomb outside BBC Television Centre in White City in March of this year.

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