Meanwhile, Egypt said Tuesday that a detained chemist wanted by Britain for questioning about the London bombings had no links to the July 7 attacks or to al Qaeda.
Government spokesman Magdy Rady said in a statement that a Cabinet meeting Tuesday reviewed an Interior Ministry report that "made clear that there is no link between Egyptian chemist Magdy el-Nashar with al Qaeda or the (London) bombings."
In Pakistan, the police chief of an eastern Punjab province town said officials were trying to find out whether the "London bombings have any tentacles in Pakistan, especially in Lahore."
"We are holding a few militants who are suspected of having links to the London suicide bombers," said Lahore Police Chief Tariq Saleem. He did not name the suspects or say how many were detained.
Lahore lies near the border with India. Many militant groups maintain clandestine offices there, and some al Qaeda operatives have been arrested in the city.
More than two-dozen representatives of the Muslim community, meanwhile, met with Blair Tuesday morning.
The community members discussed anti-terror legislation the government plans to introduce by the end of the year, saying they fear the laws may unfairly targeted their community.
"It's fair the government should ask itself whether policies such as those involving the Iraq war have contributed to this," said Dr. Zaki Badawi, head of the Muslim College. "We need a partnership between government and Muslims to show people they are not being ignored and that their concerns will be heard."
Also Tuesday, The New York Times reported that three weeks before the attacks, Britain lowered its terror alert because officials did not believe an attack was imminent.
A confidential assessment by the Joint Terrorist Analysis Center led officials to conclude that "at present there is not a group with both the current intent and the capability to attack the U.K."
The reduced threat level did not have a practical impact on anti-terrorism measures, officials said. Britain's home secretary said it did not make the country more susceptible to attack.
In the ongoing investigation, British officials were looking into whether one of the London suicide bombers used perfume bottles to make his bomb even deadlier.
Detectives are trying to retrace the four bombing suspects' footsteps, including a report in the Daily Mirror that Jamaican-born Jermaine Lindsay — one of the suspects — reportedly bought hundreds of dollars worth of perfume days before the attacks.
Scotland Yard refused to comment.
The metal perfume bottles could have been transformed into shrapnel in the blast. Investigators are still trying to determine what material was used in the four bombs detonated aboard three subways and a bus in the capital. At least 56 people were killed.
At least one person has been arrested in connection with the bombings. The man, whose name has not been released, was detained last week during a series of raids on homes in West Yorkshire, northern England, where three of the suspected bombers lived.
Clues that shed light on the bombings stretch to Pakistan. It appears that al Qaeda organizers around Europe may also have provided organizational help and could have been involved in other terrorist plots.
Shahid Hayyat, deputy director at Pakistan's Federal Investigation Agency, told The Associated Press that three of the London suspects traveled to Karachi in southern Pakistan last year – suspected bus bomber Hasib Hussain, 18, last July, and alleged subway attackers Mohammad Sidique Khan, 30, and Shahzad Tanweer, 22, in November.
He said the purpose of their trip was unclear "but I know that our security agencies are trying to get such details."
Pakistani intelligence officials have said Tanweer, born in Britain to Pakistani parents, stayed briefly at a religious school and met with a member of an outlawed domestic militant group. Pakistani agents have questioned students and teachers at the school in Lahore, and at least two other al Qaeda-linked Islamic centers.
The Times newspaper reported that Pakistani authorities know the identity of a British-born man whom London investigators believe may have masterminded the bomb plot.
"We believe this is where they could have met their mentor," the paper quoted an unidentified Pakistani security source as saying.
News reports have said that a Briton of Pakistani origin suspected of links to al Qaeda had entered Britain two to three weeks before the attacks and flown out the day before.
If true, "this would indeed be evidence of an enormous failure" of intelligence, said Charles Shoebridge, a security analyst and former counterterrorism intelligence officer.
The Home Office, which speaks for MI5, declined to comment on the suggestion that agents had missed the suspect, whose identity is not known, or on reports that at least one of the suspected suicide bombers was investigated last year by MI5, Britain's domestic intelligence service.
Questions are intensifying over the revelation that MI5 agents reportedly determined that Khan was not a threat to national security and decided against putting him under surveillance after checking him out in connection with an alleged plot to blow up a truck bomb in London.
British intelligence reportedly found that Khan, 30, a teaching assistant at a northeastern England primary school, had visited the home of a man linked to an alleged plot to blow up a London target, possibly a Soho nightclub, with a fertilizer bomb.
In that investigation, known as Operation Crevice, detectives arrested eight suspects across southern England and seized half a ton of ammonium nitrate, a chemical fertilizer used in many bomb attacks.