At Curtis House, in the London suburb of Southgate, social interaction is usually quite rare. Everyone who lives in the ugly 12-story concrete tower block minds their own business and keeps their problems to themselves. In Britain, buildings like these are called council houses, a fine sounding name for social housing. Here the state is the landlord. Hardly any of the multicultural residents pays the miniscule rent themselves, for flats which have not been renovated in years. The tiny balconies are full of washing machines and satellite dishes.

But since last Thursday morning, such discretion is a thing of the past. At 1 a.m. heavily armed police knocked on the doors of the top floor flats. Quietly, but precisely they sent the residents out into the courtyard. Then they stormed a one-bedroom apartment on the ninth floor, which turned out to be empty. They were looking for two of the suspected rucksack-bombers from the July 21 attacks: Muktar Mohammed Said Ibrahim, 27, who one week earlier is alleged to have attempted to detonate a bomb on the red No. 26 bus in Hackney Road and Yassin Hassan Omar, 24, who at the same moment detonated explosives in the Warren Street Underground station and then fled, having had a similar lack of success. Both had lived here previously and it was also here they are presumed to have made their bombs.

One week later and all that is left to remind residents of the raid are the black curtains hanging in the flat and a police van parked in front of the door. Non-residents are not allowed into the building. All questions are to be answered by Scotland Yard's press office, which is situated far away in the city center. Despite these restrictions, one resident gets straight to the point.

"Everyone here is asking themselves how these men lived here for years, became radicalized and managed to build their bombs, and yet none of us noticed anything," said 33 year-old Sam Jones. The young woman, who lived directly under the flat of the suspected attackers, reflected questions all Londoners are asking themselves. The terrorist cells that plotted the July 21 attacks weren't based in far-off Afghanistan or Pakistan but in the heart of a European metropolis.

But Why Did They Do It?

The search for the motives of the suspected bombers, their path to radicalization and their eventual momentous decision to blow themselves up, is a difficult one. The police are keeping silent. The suspects were identified with impressive speed, aided by video surveillance footage but also with the help of the general populace.

Since then, there has hardly been any new information. The British, and ultimately all of us, are left asking how and why all of this could have happened.

Of course, after these events the residents of Curtis House have their own ideas. They remember how Muktar Mohammed Said and Yassin Hassan Omar dragged heavy packets of chemicals along the halls of the tower black a few weeks ago. White powder is all that most remember but some also remember the round plastic boxes. And it was in exactly these boxes that the suspected attackers are thought later to have deposited their hand-mixed explosives to place in their rucksacks. In hindsight all this sounds highly suspicious. Residents almost appear negligent for not calling the police. But how should they have known that the pair didn't just want to mix up some paint? Why should anyone have thought ill of them, men who otherwise enjoyed playing football or liked to smoke the odd joint outside their front door?

The devil's in the details

In hindsight, a number of anecdotes yield a new picture. Residents and traders now remember small details, which didn't attract any attention before. One Turkish greengrocer has a shop a couple of blocks from the flats, where Omar often did his shopping. It became clear to him after the attacks, that the young man had changed slowly over time: that he let his beard grow and voiced his support for insurgent attacks in Iraq. Residents remember how the two young men lived increasingly isolated lives. They didn't talk to the other residents as much any more, and always looked like they were conspiring. They would also disappear off for hours into a small garage near the tower block.

Now we know a little more about Muktar Mohammed Said Ibrahim. He came to Great Britain as a teenager, having previously lived with his parents in Saudi Arabia. Once in England he had an unproblematic childhood. He was later picked up a number of times by the police. His crimes were robbery, assault and petty theft, committed for the most part as part of a gang -- and he was eventually jailed for five years. What follows is mainly speculation: apparently he encountered radical Islamism whilst in custody and abruptly gave up his lust for riches in exchange for an intensive dialogue with Allah. Likewise, it is thought he made visits to the well-known Finsbury Park Mosque, and also to training camps in Saudi Arabia and Pakistan. Nothing is certain yet though.

But not much is known about the other suspects either. Like Osman Hussein, who fled after the attacks and was arrested in Italy. He fought vehemently against being deported to London. He says that he never wanted to kill anyone. He claims that the rucksacks were full of flour and that he just wanted to give the Londoners a fright. And besides, he says, Ibrahim was the man behind it all. Osman just took the rucksack for him.

Even in Osman's case the information only trickling out: we now know he had an ex-girlfriend from Italy, where he used to live. According to what she told the Italian newspapers, he used to call her Bambi because of her brown eyes. She also said that Hamdi was a keen fan of rap music, who not only loved her but also America. He liked to see himself as a gangster. Once he got to London on the other hand Osman seems to have changed. He lived in a simple apartment, together with his girlfriend, who came from his own birthplace of Ethiopia, directly opposite the Stockwell Underground station. The girlfriend is still being held by the police for questioning. The neighbors are only slowly starting to realize who lived next to them. They also remember how the girlfriend became more and more withdrawn, and then suddenly took to wearing a headscarf when she left the house.

Live Reporting over the Cell Phone

A few kilometers away from Stockwell, in the heart of the bourgeois North Kensington district, is the Peabody Estate. Since the bombings apartment number 14 on the fourth floor of block K in the large estate next to the park has become world famous. People watching television last Friday were able to watch events unfold as police sent in masked men. In the end two naked men, Muktar Mohammed Said Ibrahim and Ramzi Mohammed, could be seen standing on the balcony of the apartment block. Again and again the suspects vomited as a result of the police's tear gas, and gave themselves up without a struggle to the masked policemen. According to evidence available so far, Mohammed is thought to be the man who wanted to detonate a bomb in the Oval Underground station. Ibrahim is suspected of laying low in his house.

Lisa Davis also became famous as a result of the live TV broadcast. She lived in the block next door and allowed audiences of British Sky News to watch the arrests via her cell phone. Now, a week on, she is still not able to explain what is supposed to have happened over the last few months to the tenant in number 14. "We all thought he was a bus driver or something. But no one here knew exactly," she says. Even the people who live in the same building only have a vague recollection of Ramzi Mohammed. Although a few tenants do remember that last February he was involved in a general complaint about the block of flats.

Ramzi and his brother Whahib, who was also arrested, are well known in the neighborhood. Over the last few months the pair spent their time in Golbourne road distributing leaflets with hatred inciting slogans. "They were both here a lot. With Ibrahim too," says the owner of a Lebanese falafel shop located directly on Golbourne road. The street runs off the Portobello road, a favorite destination for tourists because of its antique shops. The area is famous for its multi-ethnic flavor. Here in Notting Hill, poor immigrants live cheek by jowl next to rich, hip whites. No one really noticed the men. "There are so many crazy people here," says the shop owner dismissively. "Everyone tries to draw attention to themselves here."