LONDON - Police raided five residences in northern England today in connection with London's deadly terrorist bombings, Scotland Yard said.

Police searched four residences in West Yorkshire, about 185 miles from London, early today. A fifth search was under way. No arrests had been made.

The families of those missing since the terrorist bombings, meanwhile, were enduring an agonizing wait today for word of the fate of their loved ones.

The family of Michael Matsushita, a New Yorker who moved abroad in the spring of 2001, said it was likely he was dead. The 37-year-old left home Thursday to go to work and never returned.

"At this time, we've been told that there is virtually no possibility that he is alive," said David Golovner, a spokesman for Matsushita's family. "We realize the police wouldn't have told us that unless they were certain. We have given up, basically, any sort of extravagant theories about how he might still be alive."

Prime Minister Tony Blair promised authorities would hunt relentlessly for the bombers who hit three Underground trains and a double-decker bus on Thursday. Police said their painstaking investigation was moving ahead, and warned that the death toll, which went from 49 to 52 on Monday, would rise. Some 700 were injured in the attacks; 56 of those remained hospitalized.

The first of the dead was identified as Susan Levy, 53, of Hertfordshire outside London. Forensics experts have warned it could take days or weeks to put names to the bodies, many of which were blown apart and would have to be identified through dental records or DNA analysis.

Metropolitan Police commissioner Sir Ian Blair said forensic experts were scouring every centimeter of the tunnel where a bomb exploded on board a Piccadilly line train, the deadliest of the four blasts. Police said they are also scrutinizing 2,500 closed-circuit television tapes taken from cameras around the explosion sites.

"This is the biggest crime scene in England's history," Blair said, warning that the death toll would rise. "They still have to get underneath the carriages, and it is possible they will find more" bodies.

Sales of bicycles in London have climbed since Thursday's Tube and bus bombings as workers look for alternatives to public transport, the capital's biggest cycle retailer said today.

The U.S. Air Force today lifted an order barring personnel from visiting London because of safety fears following the bombings, a directive that had caused some indignation in the city after it was reported by a newspaper.

The Daily Mail newspaper said in an editorial: "We trust the 4 million Americans who come to London each year are made of sterner stuff than the U.S. Air Force."

Staff Sgt. Jeff Hamm at Lakenheath said the Air Force wanted to "ensure its personnel are as vigilant and as safe as possible."