London - British police Friday foiled a massive car bomb attack in the heart of London that could have caused 'significant loss of life' just days before the second anniversary of the major suicide attacks of July 7, 2005.
British police and forensic officers cordon off The Haymarket in central London after a explosive device was found in a Mercedes vehicle, 29 June 2007. EPA/ANDY RAIN
Government sources said the police and intelligence services were investigating a possible international link, and similarities to car bombs used by insurgents in Iraq.
Home Secretary Jacqui Smith, speaking after an emergency cabinet meeting, said Britain was currently facing 'the most serious and sustained threat.'
The counter-intelligence service MI5 warned Friday that further attacks were 'highly likely' and that alert levels would remain at 'severe,' the second-highest level.
Security experts said the timing of the planned attack suggested that it could be linked to the change of government in Britain this week, coming on the second day after Gordon Brown took over office from Tony Blair.
The attackers would have wanted to give a 'warning' to Brown to change British policy in Iraq.
Conservative Homeland security expert Patrick Mercer said the government had been warned that 'this would be a difficult week.'
Brown, saying that Britain remained under 'serious and continued threat from terrorism,' urged the public to remain vigilant 'over the next few days.'
Scotland Yard anti-terrorism chief Peter Clarke said the vehicle- born device would have caused 'significant injury or loss of life' if it had gone off early Friday morning.
'At that hour on a Friday morning, many, many people were leaving nightclubs and other places after an evening out,' Clarke said.
The device had been 'manually disabled' by officers called to the scene at Haymarket, one of London's major tourists centres where theatres, clubs, bars and restaurants are located.
Police sources said up to 60 litres of petrol in several large containers, gas cylinders and a 'large number of nails' were recovered from the Mercedes car, parked outside a nightclub.
Later Friday, police cordoned off London's central Hyde Park searching a suspect car in an underground car park, amid fears that devices could have been planted in other parts of the city.
But Scotland Yard said later the two incidents were not linked.
Brown Friday called an emergency meeting of the government crisis committee, Cobra.
'I will stress to the cabinet that the vigilance must be maintained over the next few days,' he said, in a clear reference to the upcoming anniversary of the 2005 attacks, in which 52 people died and more than 700 were injured.
The suspect car was spotted by an ambulance crew which had been called to the Tiger Tiger nightclub in the Haymarket, near Piccadilly, at around 2 am local time (0100 GMT) to assist a person, Clarke said.
They raised the alarm after seeing 'smoke' emerging from the light-green Mercedes saloon car, he added.
It was not clear whether the nightclub was a target, said Clarke. He had a 'completely open mind' as to who was behind the attack, the anti-terrorism chief said.
Earlier this month, a court in London sentenced seven men, said to have links with al-Qaeda, who the court heard had planned to use explosives-packed limousines for attacks in Britain.
Among their targets would have been nightclubs with 'all those slags dancing around,' according to taped evidence presented to the court.
'The device was almost ready to go, it was primed in a manner to be detonated shortly,' said a BBC correspondent, quoting police sources, about Friday's attempted attack.
'This was foiled totally by chance,' he added.
An unconfirmed report said the device was to be ignited by mobile phone trigger.
Security experts said it was the first time that a so-called vehicle-born improvised device (VBIED) would have been used in an attack in London.
'This is significant. These are the tactics of Iraq coming to the streets of Britain,' said the BBC's security correspondent, Frank Gardner.
Other experts said the fact that the devices were improvised was also an 'al-Qaeda' hallmark.
Brown was informed of the bomb when he woke up, said Home Secretary Jacqui Smith, adding that the new British leader was an 'early riser.'
It was revealed later that 'enhanced security measures' had been put in place at the Houses of Parliament in Westminster in the wake of the incident.
Sources said there could also be a connection with the expected sentencing next week in the trial of four suspects accused of planning a follow-up attack on tubes and buses in London on July 21, 2005.
© 2007 dpa - Deutsche Presse-Agentur 
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