SIMON ISRAEL: This CCTV image of the bus bomber was captured at Luton Station. It's been cropped from a wider picture of all four, as they were walking up the stairs to platform with their rucksacks, each one packed with primed explosives.
This is Hasib Hussein. He was 18 years old. Detectives are using this picture to appeal for help in tracing his last movements up to the apocalyptic moment; he blew himself up and killed 12 others on the Number 30 bus at Tavistock Square
PETER CLARKE: We need to establish his movements up until 9:47 AM, when the explosion occurred in Tavistock Square, and in particular, his movements between the time he left King's Cross and when he boarded the Number 30 bus.
SIMON ISRAEL: The Number 30 left Marble Arch just after 9 in the morning, ten minutes after the two bombs had gone off. It passed through Baker Street nearly ten minutes later. It reached Euston Station just after half past nine. It was then diverted into Tavistock Square because King's Cross had been cordoned off, and just after quarter to 10 the bomb exploded. At some point on that route Hasib Hussein had boarded the bus.
What also emerged today following raid on this semi-detached house in Aylesbury in Buckinghamshire, was the identity of the fourth bomber, responsible for the Russell Square attack. Police are still working through a number of variations on his name, but security sources have told Channel 4 News he's been identified as Lindsay Germain, a British resident born in Jamaica. His wife and child have been taken into protective custody.
The quartet of suicide bombers is now known: Hasib Hussein, the bus bomber; Shehzad Tanweer, who police confirmed today was responsible for the Aldgate bomb; Mohammed Sidique Khan, primary schoolteacher and Edgeware Road bomber; and the fourth, Lindsay Germain, but not yet officially confirmed.
So police now know, in fact the whole world now knows, the identity of all four British suicide bombers, and working backwards from their identities, they now have to find who they contacted, where they went, what numbers they rang, who rang them, who wrote to them, who organized them, who motivated them, who made the bombs. And all that is an enormous task that is likely to take many months.
JIM LEHRER: We get more now on one of those bombers, Mohammed Sidique Khan. Adrian Britton of Independent Television News reports on the reaction of people who knew him in Leeds.
WOMAN ON STREET: Very shocked. He was a lovely guy.
ADRIAN BRITTON: Parents at Hillside Primary School in Leeds were stunned today after learning the teaching assistant who children called their buddy was one of the four suicide bombers.
WOMAN: I think it would shock all the rest of the parents, especially from around here, and anybody else as well in Britain, to know that anybody among us could actually be planning things like this against the nation.
ADRIAN BRITTON: Did he ever show any sort of political anger?
MAN: No, never, no. He seemed quiet --
ADRIAN BRITTON: Regarded as kind as well as quiet, 30-year-old Khan had only recently moved to the Leeds home at Dewsbury and West Yorkshire, where he lived with his wife and 14-month-old daughter. Today his house remained sealed off while police continued their forensic examination.
Nearly 10 miles away, at Beeston and Leeds Khan was employed at Hillside Primary as a learning mentor, which involved helping immigrant children settle into their new schools. Today, the head teacher made a brief statement accompanied by an official.
OFFICIAL: This has been an awful shock for school, and the school will have to manage this. This is the head teacher, Sarah Balfour, and she will read a statement to you.
SARAH BALFOUR: He was 100 percent committed to the school and to the children and worked extremely hard with children and families. And as Jenny Linden said, we're all extremely shocked and finding it hard to understand.
ADRIAN BRITTON: While he harbored fanatical religious views, his younger wife, Hasini (Patel), seen with him here, was anti-Taliban and pro-women's rights. The only time he's known to have expressed political opinion was to condemn poverty in his local community. But that is hardly evidence of murderous intent. The people of Beeston may never know what turned one quiet man's devout faith into brutal hate.