Tim Golden, Michael Moss and Jim Yardley . NYTimes . 23 September
An F.B.I. investigator dusting for fingerprints at a condominium in Delray Beach, Fla., where suspects in the Sept. 11 hijackings lived.
After 11 days of intensive investigation, a collective portrait has begun to emerge of the men who guided three planes into the World Trade Center and the Pentagon and crashed a fourth in an empty field in Pennsylvania.
It is sketchy and incomplete, but its disparate pieces show a group of seemingly well-educated young men who slipped into the country and settled into bland suburban lives while they gained just enough training as pilots to take control of a passenger jet in midair.
While American officials have blamed Osama bin Laden for the attacks, they are still struggling to connect him directly to the plot. Investigators believe there were many more conspirators, but despite the efforts of thousands of law enforcement and intelligence agents, the authorities have arrested only a handful of suspects in the United States.
From interviews and confidential law enforcement documents, it appears that the hijackers lived at once secretly and in the open, taking advantage of the anonymity and freedom of a society they despised.
They arrived in the country alone or in pairs, using legitimate documents and sometimes false identities. None were known to have had criminal records, and only two appear to have come to the attention of the C.I.A. The rest, intelligence officials would say, were "clean."
They got post office boxes and e- mail accounts, driver's licenses and A.T.M. cards. Although some of them spoke little English, they barely stood out in a landscape that has grown increasingly diverse.
The men stayed away from strangers and communicated discreetly among themselves, officials said, sometimes using prepaid cellular telephones and going online at public libraries. Midlevel drug dealers might have scoffed at their tradecraft, but their security was as effective as it was low-tech.
As secret agents, they were unpolished. Two of the suspected hijackers had their Visa accounts blocked, forcing them to buy their plane tickets with cash at a crowded airport. Another was stopped for driving without a license and eventually had a warrant issued for his arrest.
In the end, though, there was a chilling focus to the madness that left thousands dead on Sept. 11. If the hijackers knew how their operation was to end, they managed to keep their resolve for months even as they strolled through malls, shopped for groceries and went to the gym.
"They'd just look right through you," recalled Gail North, 41, a longtime resident of the Valencia Motel in Laurel, Md., where five of the hijackers shared a single room the week before the attacks.
The terrorists left a spotty trail. In Laurel, an F.B.I. document indicates, agents found a duffel bag containing pilot headsets and other aviation items. Another bag recovered at Logan International Airport in Boston held a video about commercial aircraft and a will, one official said. Tracking the hijackers' finances, investigators have concluded that the operation probably did not cost much more than $200,000.
The clues are everywhere.
At a pub in the German port city of Hamburg, a patron recalls his conversations with the young Arab men who sometimes gathered in the afternoons, to talk but not to drink. "They all hated America," the patron said, referring to the circle around Mohamed Atta, who is thought to have been one of the leaders of the plot. "It's no secret."
At the Airman Flight School in Norman, Okla., there is the record of an e-mail message that arrived on March 22, 2000, from one "M.Atta." Could the school please send some information, the writer asked, about the accelerated program it had to train people as professional pilots?
And at a fitness center in Fort Lauderdale, Fla., Roxanne Caputo remembers the reserved, pleasant young man with wire-rimmed glasses who had a strangely consuming desire to learn kick-boxing, street fighting and the martial arts.
"He seemed a little tense, but that's not unusual," Ms. Caputo said. "He got in and he got out."
Intelligence officials believe that the planning for the attacks may well have gone back years, and roots of the conspiracy are visible on the dingy southern edge of Hamburg.
It was there that Mr. Atta, then a student at the Technical University of Hamburg-Harburg, began to grow more and more devout after making a pilgrimage to Mecca in 1995. At the city planning firm where he worked as an intern, his former supervisors and colleagues recall that Mr. Atta brought a prayer rug to the office and became very careful about what he ate, scraping the frosting from cakes lest they contain pork fat.
In 1999, the year he completed his studies, Mr. Atta organized an Islamic prayer group through the university students' union. German police officials now believe the group might have provided useful cover to recruit other students.
Among Mr. Atta's confederates was Marwan al-Shehhi, a student from the United Arab Emirates. Another may have been the young man with wire-rimmed glasses who later turned up in Fort Lauderdale — Ziad Samir al-Jarrah.
"What makes everything difficult is that these people were in place for a long time and had nothing to do with any terrorist or criminal acts," said a senior German security official, who spoke on the condition of anonymity. "It could be they were sleepers, with long-term orders."
In late 1999, the three Arab men reported their passports stolen on a trip to Bavaria. A spokesman for the German Interior Ministry, quoted by the newspaper Bild, said the men were apparently trying to cleanse their travel records of Afghan and Iraqi visas in order to ease their entry into the United States.
In July 2000, Mr. Atta and Mr. al- Shehhi arrived at the squat beige hangar of the Airman school in Oklahoma and asked to take a look around. The admissions director, Brenda K. Keene, gave them her standard half-hour tour: the six flight simulators, the classrooms, the airfield. The two men then thanked her and left.
Whatever their reservations about Oklahoma, Florida turned out to be a fine place for a terrorist to train. The polyglot racial mix, the transient culture of rental apartments, the simple procedures for getting a driver's license — all were helpful in concealing their preparations.
In July, Mr. Atta and Mr. al-Shehhi enrolled at Huffman Aviation International in Venice, on Florida's west coast. In October, their friend from Germany, Mr. Jarrah, began attending another Venice flight school, Florida Flight Training Center.
Across the country in San Diego, two Arab men, Nawaq Alhamzi and Khalid al-Midhar, arrived at yet another flight school, announcing that they wanted to learn to fly a Boeing jet. At that point, neither man knew how to fly at all.
Whether the hijackers were all in contact with one another is unclear. But by the summer of 2000, at least one suspected terrorist on each flight had sought or started pilot training in the United States.
A German flight student who lived with Mr. Jarrah in Venice, Thorsten Biermann, described him as an odd, dangerous man at the controls. On a round-trip flight to Fort Lauderdale, Mr. Biermann flew on the outbound segment and Mr. Jarrah manned the radio, as is customary. But on the return, Mr. Jarrah insisted on flying and handling the radio. When the weather worsened, he resisted Mr. Biermann's pleas to land and refuel. They barely made it back.
"I decided I did not want to fly with him anymore, and everyone I knew who flew with him felt the same way," Mr. Biermann said. "It was as if he needed control."
None of the hijackers seem to have become accomplished pilots. After a few chaotic lessons, the two men in San Diego were told to improve their English before they could continue; they are thought to have gone to Arizona for more training.
Ultimately, though, the hijackers did accomplish their primary goal: several instructors said the men learned to steer and maneuver but struggled with takeoffs and landings. After training on small planes at Huffman, Mr. Atta and Mr. al-Shehhi went to the Miami area in December to practice on a 727 simulator.
As they focused their training on jet aircraft, the Florida contingent shifted its base to suburban Broward and Palm Beach Counties. In all, at least 12 of the 19 suspected hijackers lived in Florida at different times.
They killed a lot of time lounging by the pool and walking on the beach. At least six joined gyms, including the World Gym in Boynton Beach.
The workouts may have been ordered by higher-ups. But three men — Waleed M. Alshehri, Wail Alshahri and Satam al-Suqami — simply clustered around the machines, never pushing any weights.
"They would just stand around and watch," said the trainer, Joe Farnoly.
Mr. Atta had a very different routine. At another World Gym, wearing grungy street clothes, he would sit at the quadriceps machine, snapping his legs furiously up and down. "Atta was working out very intensely, spastically," the owner, Jim Woolard, said. "He was crazy."
Keeping a low profile, the men chose short-term rentals that did not require extensive background checks, and they appear to have communicated almost wholly by cellphone. One man made 700 calls in the three months before the attack, a law enforcement official said.
The men in San Diego went to a mosque for help in getting settled, living for a time with an apparently unwitting Muslim professor. Those in Florida apparently avoided the local Muslim community.
If their days seemed to drag on, the nights were busier. Neighbors at various apartments and hotels described a steady traffic of Middle Eastern men and, sometimes, strange noises in the night. Federal agents later found computers and bare mattresses at one apartment, Arabic-language documents and aeronautical maps at others.
There were some signs that the men may have been looking for recruits among the many Middle Eastern pilots training along the Florida coast. On Friday, the authorities in Germany issued an arrest warrant for a young man whom one of the suspected hijackers, Mr. Jarrah, was trying to bring to Florida for pilot training, according to F.B.I. documents and interviews.
As the pace quickened, the hijacking teams began to take shape. Mr. Jarrah took a roommate in August who joined him on the flight that crashed in Pennsylvania. The group from San Diego re-emerged in a Maryland suburb; they would board the flight that hit the Pentagon.
When Mr. Jarrah and his roommate, Ahmed Alhaznawi, left Florida in August, they spoke with their landlord, Charles Lisa. "I said, `Ziad, you might have some money coming back at you. Where can I get a hold of you?' " Mr. Lisa recalled. "He said, `I'll send you a postcard.' "
On Aug. 20, a balmy day in northern New Jersey, Nawaq Alhamzi walked into a car dealership in Wayne, pulled out his MasterCard and rented a Chrysler Concorde.
He kept the car for 10 days. Then on Sept. 1, near midnight, he checked into a Maryland motel. The plot had entered its final phase.
While the hijackers' last movements remain vague, investigators believe they spent considerable time studying their targets and making dry runs. In Boston, Mr. Atta's rental car was seen on surveillance cameras moving through Logan Airport at least five times.
The men, who had already seemed so focused, turned further inward.
At the Valencia Motel in Laurel, neighbors would catch glimpses of Mr. Alhamzi and four other men sitting silently on blankets on the floor. "You never heard the phone or the TV," said Toris Proctor, who had an adjoining room.
Gail North pulled into the parking lot one day, only to be blocked by the men as they stood huddled in deep conversation. She honked to get by. They did not even look up.
Most mornings, the five men piled into a blue Toyota Corolla with California plates and drove off, taking their luggage along: dark blue or black stand-up suitcases with wheels and a few carry-on bags. When they returned they brought grocery bags and stayed in for the night.
They rarely went out alone, though the manager of a nearby adult video store recalls three visits from Mr. Jarrah. He bought nothing.
For all of their focus, the men made some silly mistakes.
Mr. Jarrah had his plane ticket sent by Federal Express to the Florida apartment he had vacated two days before. Two other suspected hijackers logged onto the American Airlines Web site only to have their Visa cards rejected because of mismatched addresses; on Sept. 5, they trudged out to Baltimore-Washington International Airport to pay cash.
In the end, though, none of the clumsiness made much difference.