Prime Minister Tony Blair (search) warned on Saturday that an "evil ideology" of Islamic extremism was bent on spreading terror through the West, and authorities on three continents widened investigations into the London terrorist bombings. The number of people confirmed dead rose to 55.

Police in the northern city of Leeds searched an Islamic shop, the home of an Egyptian biochemist and a third address for more evidence after investigators reportedly found traces of explosives in the Egyptian's bathtub.

Also, police moved the twisted wreckage of the double-decker bus where one of the bombers and 13 other people died. The bus became a symbol of the capital's worst attack since World War II.

Londoners and tourists stopped to watch as police used a flatbed truck to haul away the tangled wreckage for forensic testing.

Police also released an image captured by surveillance cameras showing all four bombers with backpacks entering the train station in Luton (search), north of London, on the morning of the July 7 attacks. Investigators say the four took a train from Luton to London's King's Cross station, where they split up to carry out the bombings.

The Sunday Times reported that one of the suspected attackers, 30-year-old Mohammad Sidique Khan (search), was scrutinized last year by the MI5, Britain's domestic secret service, but was not regarded as a threat to national security or put under surveillance. The scrutiny came during an inquiry into an alleged plot to explode a truck bomb outside a target in London, the paper said.

The inquiry looked at hundreds of potential suspects, it said.

The Metropolitan Police declined to comment on the report, and spokesmen at the Home Office, which deals with queries about national security, were not immediately available Saturday night.

The hunt for clues pointing to those who recruited, financed and supplied the four suicide bombers who blew up three underground trains and the bus focused on the men's ties to Pakistan. Authorities in Islamabad said they questioned students, teachers and administrators at one of two religious schools believed visited by one of the suspects.

Asad Farooq, a spokesman for the school, told The Associated Press that intelligence agents had been there Saturday but denied that the suspect, Shahzad Tanweer, had ever been at the school. British investigators say Tanweer, 22, carried out the bombing of the London Underground's Aldgate station.

Senior Pakistani intelligence officials said authorities were examining a possible connection between Tanweer and two Al Qaeda-linked militant groups.

ABC television reported Saturday that the FBI was looking into possible ties between unidentified people in New Jersey and a Jamaican-born Briton, whom British authorities formally identified for the first time Saturday as Germaine Lindsay, 19.

Police said he died in the worst of the suicide attacks — a subway bomb that killed at least 26 people between the King's Cross and Russell Square stations.

FBI spokesman Ed Cogswell said Saturday the agency had no comment on any pending investigations.

Authorities raised the death toll from 54 to 55 after an injured victim died overnight at a hospital. About 700 people were injured in the morning rush-hour attacks, and police said more than 40 people remained hospitalized, at least six of them in critical condition.

In a speech in central London Saturday, Blair said authorities were facing an "evil ideology" in their struggle against Islamic terrorism.

"The greatest danger is that we fail to face up to the nature of the threat that we're dealing with," he said. "And what we are confronting here is an evil ideology. ... It is a battle of ideas, of hearts and of minds, both within Islam and outside it."

Police began searching a property in Leeds a few streets away from Tanweer's home Saturday afternoon, posting guards outside the entrance and wrapping the building to block the view to outsiders. West Yorkshire police declined to comment on the raid.

Investigators also continued searching a shop called Iqra Learning Centre in the Leeds neighborhood of Beeston. The shop appeared to sell Islamic books and DVDs and offered seminars and lectures.

Two investigators wearing white protective suits could be seen inside the store before officers covered the windows with gray plastic sheeting.

The shop is about four miles from the town house of the Egyptian biochemist Magdy Mahmoud Mustafa el-Nashar, where British media reported that police had found evidence of the explosive TATP in a bathtub. Police continued searching the house on Saturday.

TATP was used by Richard Reid, the shoe bomber who was thwarted in an attempt to blow up a trans-Atlantic flight from Paris to Miami in December 2001. Reid pleaded guilty to U.S. charges and is serving life in prison.

Egypt's Interior Ministry said Egyptian authorities were interrogating el-Nashar, 33, who had studied for a semester at North Carolina State University and the University of Leeds. It said el-Nashar denied having any connection to the attacks.

Egypt is not prepared to hand el-Nashar over to Britain, Egyptian security officials said Saturday as British investigators arrived to observe the questioning. The two countries have no extradition treaty.

Britain's Labour Party, meanwhile, disclosed Saturday that bombing suspect Khan visited the Houses of Parliament last year as the guest of Labour lawmaker Jon Trickett. It said Trickett alerted security officials when he realized Khan, who had worked as a counselor at a school in Leeds, was one of the bombers.

West Yorkshire police released a statement from Khan's family saying he must have been "brainwashed" and calling on people to "expose the terror networks which target and groom our sons to carry out such evils."

Samantha Lewthwaite, the wife of the Jamaican suspect, told The Sun newspaper she refused to believe her husband was among the bombers "until they have his DNA."

"He wasn't the sort of person who'd do this. I won't believe it until I see proof," she said. The newspaper said Lewthwaite was pregnant with the couple's second child and under police protection.

In Kingston, Jamaica, a man who said he was Lindsay's father told radio station RJR he had not seen his son since the boy visited Jamaica when he was 11-years-old.

"He was quiet and calm and has his head screwed on," Nigel Lindsay said. "This was quite a surprise to me."

Nigel Lindsay said he lost contact with his son over the years but the two began having weekly phone conversations in 2004. In one conversation, the younger Lindsay confided that he had become a Muslim, the father said. He added that he had lost contact with his son two months ago.

In a statement issued Friday, the family of Hasib Hussain — the 18-year-old believed to have blown up the bus — said it was unaware of his activities.

"We would have done everything in our power to stop him," it said.