More terror in London

LONDON — Four attacks, almost simultaneous, on three subway trains and a double-decker bus. No blood and not as sophisticated, but hauntingly, unnervingly similar to deadly explosions set off by four suicide bombers exactly two weeks before — and an inescapable message that life in London now means living with the threat of terror.

"We can't minimize incidents such as this," Prime Minister Tony Blair said. "They're done to scare people, to frighten them and make them worried."

That they did.

The explosive devices were either faulty or too small to cause bloodshed, and the only reported injury turned out to be an asthma attack. But Thursday's lunch-hour blasts rattled a capital already on edge after the July 7 explosions, which killed 52 people and four suicide bombers.

Police said two men were arrested. One was detained near Downing Street, site of the prime minister's residence. The other, later released without charge, was picked up near Tottenham Court Road, close to the Warren Street subway station where one attack took place.

Authorities said it was too early to determine whether the attacks were carried out by the same organization as the July 7 blasts — or whether they were linked to al-Qaida.

But NBC News reported that British authorities told their U.S. counterparts that backpacks and explosives used Thursday were identical to those in the July 7 attacks. And the British Broadcasting Corp. reported "speculation" that the devices were so similar they may even have been part of the same batch.

"Clearly, the intention must have been to kill," Police Commissioner Ian Blair told reporters. "You don't do this with any other intention. And I think the important point is that the intention of the terrorists has not been fulfilled."

Londoners fled the three Underground stations at midday, some sprinting barefoot after leaving their shoes behind in the scramble.

Witnesses on the Underground heard a pop like a bursting champagne cork. Others smelled an odor like burning rubber. At least one reported a minor explosion in a man's backpack, and then the man muttering that something had gone wrong.

Bus passengers reported a bang on the upper level, where windows were blown out. But some witnesses said the blast wasn't loud. Witnesses first saw police running up the road, followed soon after by news cameramen lugging tripods.