The arrests continued. Ahmed Khalfan Ghailani, a fugitive wanted in connection with the embassy bombings, was captured in Gujrat, Pakistan. In London, authorities apprehended two suspects: Eisa Hindi, suspected by some officials of conducting surveillance of the U.S. targets, and Babar Ahmad, who is a cousin of Khan's and who is accused of raising money for terrorists.
Counterterrorism officials said Hindi is an alias for Issa al-Britani, who is a subject of the recently completed Sept. 11 commission report. Under interrogation, Mohammed described al-Britani as a trusted al Qaeda operative whom he sent to conduct surveillance of possible economic and Jewish targets in New York. Mohammed told interrogators that the casing mission was ordered by bin Laden.
Pakistani Interior Minister Faisal Saleh Hayat said that because of Pakistani efforts, the structure of al Qaeda "has certainly been weakened."
(Mian Khursheed -- Reuters)
The FBI has launched its own search for possible accomplices in the casing of the World Bank, the New York Stock Exchange and other financial buildings. The suspects include Adnan G. el Shukrijumah, a highly sought fugitive who lived in Florida before the Sept. 11 attacks and who officials have long feared is planning an attack. Travel records and other circumstantial evidence suggest that Shukrijumah may have helped in the surveillance of financial buildings in New York before he left the country, according to law enforcement officials.
FBI agents in recent days located one man whom they suspected of casing the World Bank and International Monetary Fund headquarters in Washington, but it was a case of mistaken identity, one official said.
Many U.S. officials and terrorism experts view with alarm the arrests in Pakistan and London, in part because of the ties between the suspects and al Qaeda's old guard. The group is closely linked by blood or friendship, and several, particularly Khan, appeared to have access to the past surveillance plans and current communications within al Qaeda.
Juliette Kayyem, head of the national security program at Harvard University's Kennedy School of Government, called the suspects "descendants of the old guard," saying: "There is still this network. It may not be as big or as powerful, but it's still around."
The computer files were heavily encrypted, indicating significant sophistication within the network, officials said. And the targets selected for surveillance suggest the influence of Mohammed who, according to the Sept. 11 commission, was preoccupied with attacking symbols of American capitalism such as the World Trade Center.
"What this is showing with al Qaeda is that they have a deeper bench than we imagined," said Bruce Hoffman, a terrorism expert who heads the Washington office of the Rand Corp. "Even when they're nailing their top operational people, there's still a centralized command structure functioning. We thought KSM was really a deathblow. It wasn't. They just caught their breath and started up again."
Hayat, however, argued that al Qaeda's top leadership has lost much of its operational control.
"That element of directness is certainly not there," he said, attributing the loss to the "arrests and also the actions . . . taken earlier" by Pakistani authorities, including a May military assault on al Qaeda training facilities in the tribal region of South Waziristan.
Hayat also suggested that some important al Qaeda planners are still at large and "sitting outside Pakistan," although "it may not be appropriate to disclose their locations."
Martha Crenshaw, a professor of government at Wesleyan University who has studied terrorism since the late 1960s, said it is difficult to determine what the recent arrests and discoveries in Pakistan say about al Qaeda's viability.
"We don't know if this is the last gasp of what's left being rounded up, or whether they are much more resilient than we thought," Crenshaw said. "What we're not seeing is a lot of evidence of new leadership."
Crenshaw also noted that Khan's involvement in the sting may indicate a breakdown in loyalty to the outlaw network.
The Bush administration generally views the recent arrests and intelligence discoveries not only as a window into al Qaeda's operations, but also as a serious blow to what remains of the network. In a background briefing Thursday in Washington, one senior administration official characterized the arrests as "a strategic success against al Qaeda, as opposed to the wrapping up tactically of a single cell."
Some Pakistani intelligence officials are more cautious. They say that such arrests may have a limited impact both on al Qaeda, which they view as already dispersed, and Islamist terrorists who are inspired by bin Laden but not beholden to him.
"Almost every important al Qaeda arrest in Pakistan reinforced our analysis that al Qaeda breakaway cells, each consisting of no more than two dozen people, have emerged as more lethal and committed stand-alone groups," one Pakistani intelligence official said.
Lancaster reported from Islamabad. Staff writer Mike Allen in Washington and correspondent Kamran Khan in Pakistan contributed to this report.