LONDON, July 12: Police identified four men on Tuesday whom they suspected of carrying out last week’s London bombings, raising the prospect that western Europe may have suffered its first suicide attack.

Police said it was ‘very likely’ that one suspect had died in the blasts on London’s transport network, which killed at least 52 people and injured 700, and were trying to work out if all four bombers had blown themselves up deliberately.

If they did, it would be the first time that suicide bombers, who have wreaked carnage from the streets of New York to Israel and Iraq, have struck in western Europe.

The British government has already said last Thursday’s attacks bear the hallmark of militants loyal to the Al Qaeda movement.

“The investigation quite early led us to have concerns about the movements and activities of four men, three of whom came from the West Yorkshire area,” said Peter Clarke, head of the anti-terrorist branch of London’s Metropolitan Police.

“We are trying to establish their movements in the run-up to last week’s attacks, and specifically to establish whether they all died in the explosions.”

He said police had found personal documents with the names of three suspects close to the scene of three of the blasts.

One of the suspects probably died in the blast at Aldgate Underground (subway) station, Mr Clarke said.

“This is a new level of radicalization for the United Kingdom,” he said. “Suicide bombings are commonly accepted to be the most dangerous and difficult to thwart.”

Seven prime suspects in last year’s Madrid train bombings blew themselves up three weeks after the attacks when surrounded by police in a flat in a suburb of the Spanish capital.

But if the London attacks are confirmed as suicide bombings, it would be the first time in western Europe that militants have blown themselves up to inflict mass civilian casualties.

The four men travelled to London on the day of the blasts and were recorded on closed-circuit television carrying rucksacks at King’s Cross rail station shortly before 0730 GMT, police said.

Three bombs exploded within 50 seconds of each other at 0750 GMT on subway trains that had all passed through King’s Cross. A fourth exploded 57 minutes later on a bus not far away.

HOUSES SEARCHED: The revelations came on a day of rapid developments. Police searched six houses in and around the northern English city of Leeds, including the homes of three of the four suspects.

One man, a relative of one of the suspects, was arrested. Police seized materials that they said might be explosives.

Some 500 people were evacuated from red-brick terraced streets in a largely rundown, racially mixed area of the city of 715,000 people.

Its Muslim population of around 30,000 is one of the largest in Britain, and in May 2001, it was one of several northern towns that saw rioting between south Asian and white youths blamed on ethnic, religious and racial divisions.

Police said they had also seized a vehicle in a car park in Luton, another town with a large Muslim population near London, which they believed was linked to the attacks.

“I have to tell you that this investigation is moving at great speed,” Mr Clarke said.

The raids came amid growing frustration at what many grieving relatives feel is slow progress in formally identifying the victims of the bombings.

By Tuesday afternoon, authorities had named just three of the dead. Two more had been formally identified but their names had not been released.

In contrast, during the Madrid bombings last year, forensic scientists had identified about 50 bodies by the end of the day of the attacks.

After a wave of public scorn and indignation, the US Air Force rescinded an order banning its personnel at two air bases in Britain from visiting London in the wake of the bombings.

London police chief Ian Blair had urged the Americans to reverse their decision as British authorities had been telling people to return to work and normality.

PARLIAMENT SCARE: A security alert led police to seal the entrances and exits to Britain’s parliament on Tuesday.

The scare was one of many in the British capital since Thursday. All have so far proved to be false alarms. —Reuters