BARCELONA, Spain — On July 7, 1998, thieves snatched a passport from a car driven by a U.S. tourist here, a small rip-off that became a footnote in a major act of terrorism.
The passport belonged to an Iranian American medical student from St. Louis. It made its way into the hands of Ramzi Binalshibh, an alleged coordinator of the Al Qaeda cell in Hamburg, Germany, that carried out the Sept. 11 attacks.
Binalshibh allegedly used the name on the passport in the summer of 2001 when he wired money to Oklahoma to pay flight school tuition for Zacarias Moussaoui, the accused "20th hijacker." Moussaoui and Binalshibh are now in U.S. custody.
The stolen passport is another clue indicating that a support network in Spain and Germany figured in the Sept. 11 plot. The precise role of the network, like the path of the passport from Barcelona to Hamburg, remains one of the mysteries of the attacks.
Spanish authorities say the investigation could help identify accomplices of the Sept. 11 hijackers in Europe and the United States, where little progress has been made finding henchmen. It could also dismantle a support structure that might still be dangerous, investigators say.
The top suspects are Syrian immigrants in Spain and Germany related by friendship, family and business. They are older, better educated and more Western than many Al Qaeda suspects in Europe. Investigators believe that the Syrians served as deep-cover mentors, recruiters, financiers and logistics providers for the hijackers -- elite backup for an elite attack team.
"The Syrians are classic 'sleepers,' " said a Spanish law enforcement official. "Cold War-style, they were well established and went about their business. But when Al Qaeda needs them, they are here, ready to help."
More than a year of detective work has produced significant leads connecting suspects to one another, Al Qaeda and the plot, according to investigators and court cases in Spain and Germany:
* The suspected boss of an Al Qaeda cell in Madrid was an associate of the Syrian German operative who allegedly recruited hijacker Mohamed Atta.
* A Syrian-born businessman in Hamburg is under scrutiny because of alleged contacts with Sept. 11 suspects.
* Suspected members of the support network converged in Spain around the time Atta and Binalshibh met there in July 2001 in what is believed to have been a key step in the Sept. 11 planning.
Investigators are still building the case, however. Prominent suspects have not been arrested. And defense lawyers say authorities have mistaken a tangle of friendships, family obligations, business deals and religious donations for a conspiracy.
The lawyers cite the financial activity of Mohammed Galeb Kalaje Zouaydi, who is accused of using a Madrid real estate firm and a Saudi trading company to send money to the Hamburg suspects, a would-be assassin in Yemen and an Al Qaeda courier who is Galeb's brother-in-law. Galeb's family says he has legitimate explanations for the hundreds of thousands of dollars under suspicion. They say he has stumbled into a nightmare.
"I've been married to my husband for 18 years, and I know how he thinks, how he is," said Galeb's wife, Hazar Dabbas. "I know he is innocent. I am going to defend him until he overcomes this. He works very hard for his children. This case changed everything for us for no reason."
Police say they were able to map Al Qaeda's structure in Spain and elsewhere during six years of surveillance of the Madrid cell, which had ties to Valencia, Granada, Barcelona and other Spanish cities. The suspected foot soldiers include young North African thieves and drug dealers who allegedly stole identity documents and credit cards for use by Islamic militants en route to Afghan training camps and Bosnian battlefields.
But the main suspected players in Spain and Germany are middle-aged merchants with families, comfortable lifestyles, busy travel schedules -- the stuff of immigrant success stories. Half a dozen are from the Syrian city of Aleppo, a hub of Arab history where Atta researched an academic thesis. Several of the suspects even resemble one another: imposing, bulky, bespectacled men with full beards.
Spanish investigators are counting on police in half a dozen countries to help prove that the suspects were accomplices of the hijackers. Some leads may fizzle otherwise: In July, police arrested Galeb's former business partner after finding videotapes of the World Trade Center and other potential U.S. targets he filmed in 1997. He was released on bail, but authorities asked the FBI to help investigate men seen on the videotapes and other possible U.S. associates of the Spanish suspects.
"We are waiting for information from Britain, from the Americans, from evidence found in Afghanistan," a Spanish law enforcement official said. "You reach an impasse where you depend on international cooperation."
Already, investigators have found previously undisclosed connections between the Madrid and Hamburg suspects.