The Second Plot: Copycats or Co-Conspirators?

They were two terrorist cells united by, if nothing else, the same target: the London transport system.

By the time the first bombers reached their targets on the morning of July 7, three of them had traveled 200 miles.

Exactly two weeks later, the second group struck just 200 yards from a ground-floor apartment where one suspect lived with his wife and three children.

The two groups of young men were separated by more than miles. Three of the July 7 bombers were British-born sons of a Pakistani immigrant community that has carved out a solid life in the weary industrial neighborhoods of Leeds in Britain’s north. One was a schoolteacher; another worked in his father’s fish-and-chips shop.

In contrast, at least three of the July 21 suspects came to Britain hardened by youthful odysseys out of the despair of Somalia, Eritrea and Ethiopia. They never got past the margins of British society, sliding into a gray world of unemployment, welfare, public housing and crime.

Yet authorities say they came to the same violent conclusion: wreaking havoc in the capital by attacking three Underground trains and a bus with backpack bombs. The first plot killed 56 people, including the bombers. The second could have inflicted the same carnage, but the explosives failed to fully detonate because of a bomb maker’s mistake, police say.

Police were trying to make sense of the differences and similarities Saturday as they questioned four July 21 suspects and another London man thought to be a possible fifth would-be bomber.

Detectives confront a fundamental mystery: Were the two plots part of a terrorist campaign by an international network that cobbled together multi-ethnic cells from different cities and disparate backgrounds? Or was the second strike a copycat attack by an unrelated group, as Italian police say one of the July 21 suspects said in a confession Friday?

Despite the reported confession and the contrasts between the Leeds and London cells, most investigators think there has to be a link because of the remarkably similar explosives, targets and methods.

“I think there’s plenty of linkage,” said a British anti-terrorism official who spoke on condition of anonymity. “Two attacks within two weeks with very similar modus operandi. The significance of that alone shouldn’t be discounted. What has to be determined is how those linkages work.”

British anti-terrorism agencies are also struggling to understand the threat embodied by two homegrown cells that got past their defenses.

“We are looking at this terrible problem of groups that are not really run from anywhere,” said Charles Heyman, a defense expert with Jane’s Information Group. “You have local offshoots drawing from Al Qaeda doctrine. They are operating almost totally independently, and that makes the intelligence picture very difficult. You’ve got to have indicators for intelligence, especially electronic indicators. They just aren’t there. They are getting under and around the intelligence screen.”

Although London’s police chief has said the attacks came “out of the blue,” at least one bomber in the July 7 attack had surfaced before, in the investigation of a foiled plot last year involving a network spreading from Pakistan to Britain to North America. He and two others had traveled to Pakistan, where investigators think they were radicalized and possibly trained by Al Qaeda operatives.

Meanwhile, police say the July 21 suspects are products of militant circles centered on the Finsbury Park Mosque in north London, a notorious crossroads of extremism. Their alleged leader was a convicted robber and jailhouse convert.

One suspect in the would-be bombings who was captured in Rome on Friday lived only 200 yards from the Stockwell Underground station in the heart of South London’s African British community. That station became the launching pad from which three of the men embarked on murderous missions: One bomb partially detonated just minutes after a train left the Stockwell platform.

The choice of target would seem a defiant statement on home turf, evoking a kind of fierce street gang mentality as much as Islamic terrorist ideology. The detainees are suspected of an attack not only on their own country, but on their own neighborhood.

In his confession in Rome, the Ethiopian-born, 27-year-old suspect insisted that he was part of a self-contained, improvised group with no links to the Leeds crew, authorities said.

The suspect was first identified publicly as Hussain Osman, but a senior Italian anti-terrorism official said his real name was Hamdi Isaac. In his confession, as described by the official, the suspect said the four militants had been fired up by the war in Iraq and other jihadi causes. Inspired by the deadly July 7 attacks, they decided to carry out a follow-up strike, prepared their own bombs and followed the script of the previous attacks, according to the confession.

A high-ranking Italian law enforcement official said he could not rule out the possibility that the second strike was the work of a separate network of East Africans. Militants with that ethnic background have surfaced in previous cases of networks sending jihadis to Iraq, he noted.

“So you might find people who had been in Iraq, or were radicalized by Iraq, who had been preparing their own plot,” the law enforcement official said. “When they see July 7 happen, they say, ‘We want to do something to emulate this.’ To legitimize themselves and say: ‘We exist too.’ ”

On the other hand, the Rome suspect may not have known of connections to the Leeds cell. The networks are loose and protean, stealthily crafting new networks out of the remnants of old ones. The investigation has to seek a figure capable of orchestrating two cells in isolation from each other.

“If I’m investigating this, I have to track down the common denominator,” said Louis Caprioli of the GEOS security firm in Paris, the former anti-terrorism chief of France’s DST intelligence agency. “It could be a place of radicalization, an individual, a giver of orders. I am convinced the second group is linked to the first.”

If an international network was involved, investigators think it can be traced to Pakistan because of the ties between the Leeds bombers and the Pakistani-based group that plotted the foiled attack on Britain last year.

But foreign masterminds are elusive, relying largely on local infrastructures. After last year’s train bombings in Madrid, police rounded up several dozen front-line suspects in Spain. Although police also identified a few Al Qaeda fugitives as potential leaders, those men have not been charged.

In Britain, the search for links between London and Leeds could focus on several figures. There is Germaine Lindsay, the fourth dead bomber from July 7. As a Jamaican convert to Islam living in Luton, he could have been a nexus between the British Pakistanis who died along with him and the African British militants now under arrest.

There is also the mysterious Haroon Rashid Aswat, an alleged Al Qaeda figure with longtime ties to extremist circles in both London and the Leeds area. Investigators are trying to determine whether he was in telephone contact with some of the Leeds bombers.

There are doubts about his role, but his travels and contacts -- from Oregon to Africa to Afghanistan -- make him intriguing. He has been detained in Zambia.

Another mystery: the bomb maker. Because the British police retrieved five mostly intact backpack bombs July 21, they have a wealth of forensic evidence. British security services are still investigating an Egyptian chemist who was arrested in Cairo on July 15 because he had rented the apartment in Leeds used as a bomb factory. Magdy el Nashar, 33, remains in custody and under suspicion, the British anti-terrorism official said Friday.

“I don’t think we should discount him,” the British official said. “It is a curious coincidence of location and expertise. There is certainly interest.”

The attacks revealed an essentially homegrown threat, to the surprise and dismay of a government that thought the most urgent danger was from foreign terrorists.

To some extent, the British ran into the same problem that other countries have: the sheer difficulty of monitoring large Muslim communities when a barrage of intelligence forces police and spies to make hard choices.

But the failure to detect a lethal cell in Leeds may also reflect the fact that British anti-terrorism services tend to be stronger in the capital than the provinces, said Caprioli, who worked closely with British counterparts while at the French DST.

“The bombers prepared outside London, where the intelligence services are less established,” Caprioli said. “The contacts there are local police, who don’t have the same feel for the networks. That’s different from France or Italy, where you really have an intelligence presence throughout the countries.”

In fact, British security forces had been beefing up their undercover presence in northern England when the attacks occurred, the British official said.

Britain’s strong traditions of free speech have made London a haven for clerics and activists from across the Muslim world. British spymasters have opted to let even aggressive ideologues operate openly in order to watch them more easily.

Now the British government has proposed tough laws that would punish speech that incites violence, regulate Islamic bookstores and make it a crime to train in foreign terrorist camps. The attacks have driven home the power of words to spur terrorism, whether by organized networks or local amateurs, some experts say.

“If the British have some fault in this, it is to have let places like Finsbury Park Mosque function for too long,” an Italian intelligence official said. “Terrorist attacks are born in jihadi preaching, which is the first step toward recruitment. They allowed the first steps to be taken. That’s very important to understand. The objective of course was to have better control, but some fish always slip through the net.”