Britain's most senior police chief has said the perpetrators of yesterday's attacks on London's transport network meant to kill. However, Metropolitan Commissioner Ian Blair said it was too soon to say if the failed attempt to set off explosions at four locations were linked to the bombing attacks two weeks earlier which claimed 56 lives.
The political and security fallout from the July 7th bombings took a dramatic turn, meanwhile, as senior police chiefs last night pressed the government to extend their powers to hold terror suspects for up to three months; allow the use of telephone intercept evidence in courts; and think again about the creation of a single border police force for Britain.
Speaking after a day of drama, localised panic and widespread disruption and confusion in the capital, Sir Ian said it was his understanding that at least some of the devices had failed to explode at the Oval, Warren Street and Shepherd's Bush underground stations and on a number 26 bus in London's East End.
The commissioner also confirmed that the failure of yesterday's attacks had yielded a potentially "significant breakthrough" in terms of forensic evidence left at the four crime scenes.
British prime minister Tony Blair adjourned talks with Australian prime minister John Howard and cleared his diary to chair a meeting of the cabinet's contingency Cobra committee as news of the latest terror attacks broke early yesterday afternoon.
However, he appeared at a delayed Downing Street press conference shortly before 4pm to signal his resumption of normal business.
As police established control of the situation around the crime scenes, Mr Blair said: "We can't minimise incidents such as these, all I would like to say is this - we know why these things are done, to frighten people and make them anxious and worried. Fortunately, in this instance there appears to have been no casualties. We have just got to react calmly."
However, relief was tempered by the realisation that another group of terrorists had struck and that, as Sir Ian said, their intention "must have been to kill". He told a news conference: "Clearly the intention must have been to kill. You do not do this with another intention." But he added: "I think the important thing is that the intentions of the terrorists have not been successful."
While it had been "another difficult day" for the capital, he said: "London has gone past this point again. We are back to business."
The commissioner said there was obviously "a resonance" to the four previous attacks - again virtually simultaneous, on three tube trains and a bus - but that it was too early to say whether this was the work of the same terrorist network.
Security experts echoed Sir Ian's hope of a forensic breakthrough, one suggesting that the devices that failed to explode could provide "a treasure trove" for investigators seeking to establish any connection to the July 7th bombings. The type of explosives used could possibly point to the origin of the bombs and whether there was a foreign connection.
Witnesses reported small explosions, white smoke, a smell akin to burning tyres and abandoned rucksacks at the site of the incidents at Warren Street and the Oval tube stations and on the bus. One man reportedly threatened to blow himself up and then ran off, with a number of passengers unsuccessfully giving chase.
Throughout much of the afternoon police attended what was called a major incident at University College Hospital near Warren Street. An internal memo told hospital staff to be on the lookout for a man said to be over 6 ft tall with wires reportedly protruding from his top.
There were conflicting reports from Scotland Yard and political sources about at least two arrests reportedly made through the day. In extraordinary scenes in Whitehall, across the road from Downing Street, one man was forced to the ground before being arrested and taken away at gunpoint. However, Sir Ian said the arrest in Whitehall and the incident at the hospital were "entirely unconnected events".
The commissioner said it was unclear how many people had taken part in yesterday's attacks. Having said the July 7th attacks bore all the hallmarks of an al-Qaeda operation, he was not yet ready to make a similar judgment about yesterday's attacks.
The proposals for a sweeping extension of police powers to hold terrorist suspects for up to three months was made by the Association of Chief Police Officers at yesterday's scheduled security summit at Downing Street. ACPO argued that the present maximum of 14 days was insufficient in complex terror cases.