CBS/AP/ February 11, 2009, 7:15 PM

Dramatic Raids Net Bomb Suspects

Last week's images showed them escaping from botched terror attacks, one wearing a "New York" sweat shirt. Cameras on Friday captured them bare-chested on an apartment balcony, arms flung overhead in surrender after eight days on the run.

In hours of high drama from London to Rome, police netted the remaining suspects in the failed transit bombings — without firing a shot. At least three of the four were of East African origin.

But no one called the investigation over, and counterterrorism officials were searching for possible links between al Qaeda operatives in Pakistan and cells that carried out attacks on July 7 and July 21.

CBS News Correspondent Richard Roth reports police are cautioning that the situation is still not safe because the recruiters and planners behind the deadly July 7 attacks — and the bombing attempts last week — are still at large.

Images captured on closed-circuit television cameras during the failed July 21 attacks helped investigators find the men, and interrogations of the suspect captured first earlier in the week, 24-year-old Yasin Hassan Omar, may have helped as well in what police have called their most extensive investigation ever.

Peter Clarke, head of Scotland Yard's anti-terrorist branch, sounded a cautionary note as he announced the arrests.

"Despite the progress that has been made with the investigation, we must not be complacent," Clarke warned. "The threat remains, and is very real."

The dramatic raids began in late morning in London as black-clad police armed with stun grenades and gas masks pointed assault rifles at the doors of suspects on the outskirts of Notting Hill. Two young children stumbled into the standoff a floor below a suspects' apartment, and an armed officer tried to shoo them away from his dog.

Above them, a police team shouting for "Mohammed" forced two suspects to strip to their underwear and eventually emerge onto a narrow balcony, where television cameras recorded them with their hands above their heads.

In Rome, police arrested a Somali-born British citizen at the apartment of his brother, who was also taken into custody. On Friday night, a police expert — wearing white gloves and a jumpsuit to avoid contaminating possible evidence — could be seen working inside a lighted room in the apartment.

Authorities have probed a possible link between the failed July 21 attacks and the July 7 suicide bombings, which killed 56 people, including the four bombers. Three of the British suicide attackers had ties to Pakistan, where they were born.

They have a working hypothesis that the cells did not know each other, but were connected by a more senior operative higher up an organizational chain, said a counterterrorism official, who spoke on condition of anonymity because investigations are ongoing.

Authorities also are theorizing the plot may be linked back to Pakistan and the al Qaeda organization there. However, "we are not there yet in terms of proving it," the official said.

The official said the newly detained individuals are being questioned, and authorities haven't ruled out that more cells may be on the loose. It's also not yet clear why a team of young men of mostly Pakistani descent and a second team of African men were put together.

A British police official said of any potential cell links: "Yes, it is possible they may not have been known to each other but had a conduit working between them for someone else."

On the links back to Pakistan and al Qaeda, the official said it was too early to make that connection and noted police have 20 people in custody for questioning, with the inquiry expected to last several months. The official was not authorized to give his name.

One man arrested in the apartment complex near Dalgarno Gardens street identified himself as Muktar Said Ibrahim, 27, Clarke said. Police believe he planted explosives on the No. 26 bus in Hackney, east London. Ibrahim, also known as Muktar Mohammed Said, immigrated from Eritrea in 1990 and became a British citizen in 2004.

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