In the weeks since Sept. 11, German investigators have been hunting terrorist "sleepers."
It now appears they have found one.
Earlier this week, officials said they'd caught a Turkish university student as he was leaving the country. In his bags were detonators, a CD-rom with instructions for conducting an Islamic holy war, and a protective suit against chemical and biological weapons, prosecutors said.
This success comes as Germany has begun to adopt new measures - including computer profiling - to spy on the large numbers of Muslims living within its borders.
US and German officials announced Tuesday in Washington that they had identified three Al Qaeda operatives from Germany believed to have been closely associated with three of the Sept. 11 hijackers, including Mohamed Atta. The three suspects - Said Bahaji, thought to be a Moroccan; Ramsi Binalshibh of Yemen; and Moroccan Zakariya Essabar, 24 - are now the target of an international manhunt.
Meanwhile, questions are being raised over how German authorities failed to see signs of the terrorist cell that was developing in Hamburg before the attacks on America.
"We were completely naive," says Gerhard Vogler, head of one of Germany's largest police unions.
Since Sept. 11, Germany's rusty and underfunded interior security system has been playing catch-up, reopening investigations of suspected Islamic extremists and keeping close track of religious groups already suspected of extremist tendencies.
The arrest of the Turkish student at Frankfurt airport was the sixth in Germany since Sept. 11, and came as investigators continued tracking the intricate terrorist cell in Hamburg, where it is believed the Sept. 11 attacks may have been planned.
So-called "sleeper" agents of such cells live unobtrusively until they receive a signal to activate an assigned plan.
Vogler says that the German intelligence system had been cut back since the fall of the Berlin Wall. With no communists to spy on, politicians saw no real need for an active intelligence system and began trimming funding. Law enforcement authorities had to reassign many of the officers involved in spying or dismiss them.
In the meantime, Muslim extremist groups took advantage of Germany's favorable immigration rules, large Muslim population, and fierce information-protection laws, and found a way to hide, say security experts.
"They found a heterogeneous population with a big Muslim diaspora," said Kai Hirschmann, a terrorism researcher at the Federal College for Security Studies. "Of course, 99 percent of the Muslim population is like you and me, but there is always a percentage you can describe as extremist."
Up until Sept. 11, authorities had categorized 3,250 people in Germany as Muslim extremists. But they had little idea of the extent and density of the network that lay behind those people.
Hirschmann says there is little in Germany's past experience with terrorism - including a Palestian group's attack during the 1972 Munich Olympics, and the political assassinations carried out by the leftist Red Army Faction in the 1970s and 1980s - that could have prepared it for the complexity of the Al Qaeda network.
"This was no small operation, like in the past," says Hirschmann. "Al Qaeda is like Terror Holding," he adds, comparing the network, which Osama Bin Laden is suspected of heading, to a multinational corporation. "It's a fight that we've had absolutely no experience in."
Government and security experts say measures such as computer-aided profiling, which was reinstituted by Germany's 16 state governments Oct. 1, are increasingly necessary in weeding out Islamic extremists.
Investigators have indicated that they are scrutinizing primarily Muslim men of Arab descent who are financially independent, study some technical or professional trade, and who make frequent trips out of the country. Other criteria are being kept secret. State and federal police are also tight-lipped about whether anyone has been brought in for questioning as a result of the method.
Faud Zaidan and other Muslim students at Darmstadt's Technical University, just south of Frankfurt, say that the increased vigilance unfairly targets them. "It's a form of racism," Zaidan says.
The university was compelled by a court order to give all of Zaidan's personal data to the state police. Investigators will now run that information, and the information of close to 200,000 Muslims studying at Germany's universities, through their computers in the effort to ferret out terrorist suspects.
Authorities "should not forget that there are 400 Muslims who died in New York," says Zaidan, leader of the Darmstadt school's Islamic Student Organization. "We are also victims of the attack."
Germany is also considering additional counterterrorism measures.
Earlier this month, German Interior Minister Otto Schily introduced his second package of proposals to the Bundestag, Germany's parliament. He proposes enlarging the country's border guard to include a new aircraft protection unit akin to US sky marshals, and giving new powers to the Federal Office of Criminal Investigation so that it may undertake investigations without probable cause.
Schily has also recommended changes to the national identification card to include features such as the cardholder's fingerprints. He also wants to make it easier to ban extremist groups that operate under the guise of religious groups, and make it easier to deport extremists or violent foreign nationals.