London police say they have unexploded bombs and other evidence that they hope will lead them to the perpetrators behind four small explosions on the mass transit system Thursday. Authorities say the attackers apparently tried, but failed, to mimic bombings that killed 56 people two weeks earlier.
Police say the latest attacks were intended to cause mass casualties, but for some reason the bombs did not explode with the same destructive force of those planted on July 7.
That has left authorities optimistic they can track down the perpetrators of Thursday's incidents, where small explosions were recorded on three subway trains and a bus. There were no deaths, but one person was wounded.
London Transport Police Deputy Chief Constable Andy Trotter said there are many leads the police are pursuing in their search for the culprits. "It's a good opportunity to get forensic material. They are looking for people this time. And we've got good witnesses, hopefully good [closed-circuit television], so it's a fast-moving investigation," he said.
Authorities hope the unexploded bombs and the backpacks containing them might yield fingerprints, DNA and other useful evidence.
A former police commander, John O'Conner, told British television London came close to another large-scale disaster. "This was a mirror image of what happened on the 7th of July, and the bomb-maker got it wrong. The detonators seemed to work but the main charges didn't go off. Now that is extraordinarily fortunate for the people that were passengers adjacent to those devices," he said.
London commuters are returning to mass transport with a mixture of apprehension, resignation and determination.
One man said, "everyone's a bit shaky, I think. There are a lot of nervous people out there. It's to be expected, but we have to get on with it. We're not going to let them win."
Another added, "you can avoid the Tube [subway] or you can avoid the buses for the next three years, and the day you get on it something could happen, you know. As tragic as it is, I mean, what do you do?"
A group called the Abu Hafs al-Masri Brigades has claimed responsibility for Thursday's explosions in a posting on an Islamic web site. The same group, which says it is part of the al-Qaida terrorist network, also has claimed responsibility for the July 7 bombings, though authorities have not authenticated that claim.