U.S. says it has identified hijackers
Probe stretches around the world

WASHINGTON (CNN) -- Top U.S. officials said Wednesday they know the identities of many of the hijackers on each of the four flights that crashed Tuesday -- two toppling the World Trade Center and a third heavily damaging the Pentagon in the worst terrorist attacks in U.S history.

"We have, in the last 24 hours, taken the (passenger) manifests and used them in an evidentiary base," said FBI Director Robert Mueller. "And have successfully, I believe, identified many of the hijackers on each of the four flights that went down."

The fourth flight crashed in a field in Pennsylvania.

Meanwhile, people were taken into custody by U.S. agents as the investigation into Tuesday's deadly air crashes intensified on several fronts. The individuals have not been arrested and they have not been described as suspects.

Federal agents were also investigating whether separate cells of terrorists were involved in Tuesday's attacks.

The massive investigation, involving hundreds of agents and numerous law enforcement agencies, played out on several fronts across the United States as the hunt for the culprits intensified.

Among the latest developments:

-- In Florida, homes were searched in various cities and people were taken into custody for questioning. Sources said the individuals may be able to provide "important material information" related to the attacks.

-- Three men were detained in Boston after police and federal agents raided a hotel.

-- Each of the four crashed jetliners are believed to have been flown by hijackers trained as pilots in the United States, said Attorney General John Ashcroft.

-- In Hamburg, Germany,two apartments came under the scruting of the BKA, the federal criminal agency. Authorities searched one apartment at the request of the FBI, a police spokesman said. Agents found that one of the apartments had been empty since February and the resident of the other did not match the name given by the FBI, so the second apartment was not searched.

-- In Providence, Rhode Island, an Amtrak train was stopped Wednesday after authorities demanded its halt. At least one man was arrested for carrying a concealed weapon. He was led away from the train station in handcuffs. Authorities said it appeared the man had no connection to Tuesday's disasters.

Boston is a focus of the investigation because two of Tuesday's four hijacked flights originated at Logan International Airport. A car was also impounded at that airport and suspicious material was seized. A local newspaper said the material was in Arabic.

At a Wednesday afternoon news conference, Ashcroft and Mueller acknowledged that people had been detained, but said no arrests had been made.

Mueller said investigators are using passenger manifests of the four crashed airliners to identify who was involved in the disasters. Mueller said authorities are "attempting to create the travels" of the suspected terrorists.

"We will leave no stone unturned to find those responsible for the tragedies."

Hunt widens in Florida
In Florida, various people were questioned as the hunt led to aviation schools in that state.

At least 10 FBI agents searched two side-by-side houses in Vero Beach and took one man into custody for questioning.

The immediate neighborhood was temporarily evacuated after FBI agents knocked on doors and said there was a bomb scare. Residents have been allowed back in their homes.

Little information was available after the nature of the search.

Landlord Paul Steineling said he rented the house to Adnan Bukhari, a man who said he was a commercial pilot from Saudi Arabia. The man, who lived with his wife and three children, said he was attending a local flight school.

The family, the landlord said, moved out over the weekend.

The FBI took into custody for questioning one person who rented one of the two houses. He is believed to be an acquaintance of another man tied to the flight safety school.

Earlier, one search warrant was served in the Vero Beach area of Indian River County, but no details were available. Other areas in Broward County were also under scrutiny, but one law enforcement official said no solid leads had materialized.

In Venice, several people were taken into custody in connection with Huffman Aviation International Flight School, including the man who runs it.

Rudi Dekkers, the owner of Huffman Aviation International, said the FBI had inquired about a student. Dekkers said he handed over some documents to the FBI. The FBI also went to the home of Chalres Voss, a bookkeeper for the school, who housed two students from a Middle Eastern country between June and November of last year, according to police and the local sheriff's department.

FBI agents also visited a restaurant in Hollywood -- north of Miami -- showing patrons pictures of two men of Middle Eastern origin and asking anyone if they recognized the men, according to police and a bartender at Shuckum's restaurant.

In Coral Springs, police said they accompanied the FBI Tuesday night to a home where one of the suspected hijackers may have lived. Police also issued a lookout alert for two cars -- a 1989 two-door red Pontiac with the license plate D79-DDV or DVD and a four-door Oldsmobile with the license plate VEP-54N -- but it was not clear why those cars were being sought.

In Daytona Beach, the FBI was seeking search warrants and a car was towed by authorities for examination.

Boston probe looks at car
Heavily armed police and FBI agents swarmed the 36-story Westin Hotel in the Copley Square area of Boston. Three men had been detained after authorities searched that hotel.

Law enforcement officials confirmed that a car was seized at Boston's Logan International Airport and that suspicious materials were found. The Boston Herald said there were Arabic language flight training manuals in the car, but an FBI spokeswoman refused to confirm or deny that report.

Meanwhile, in Portland, Maine, police said that two individuals who traveled by plane from that city to Boston were under investigation.

"I can tell you those two individuals did get on a plane and fly to Boston early yesterday morning," said Portland Police Chief Mike Chitwood. "I cannot tell you who they are, I cannot tell you where they came from. I can tell you that they are the focus of a federal investigation."

He said that the two were recorded on videotape as they went through the Portland Jetport's security cameras. It was not immediately clear whether the two individuals were on any of the hijacked planes.

Maine authorities said a car -- a rented silver Nissan Altima with Massachusetts plates -- was seized from the Portland airport Tuesday evening. Authorities believe the two men -- possible hijackers -- used that car to travel to the airport, where they boarded an early morning commercial flight to Boston.

Phone calls may provide clues
The United States also intercepted two phone calls made after Tuesday's terrorist attacks against the Pentagon and New York's World Trade Center, and the conversations were between members of al Qaeda, an organization sponsored by suspected terrorist Osama bin Laden.

In those conversations, U.S. law enforcement officials said, the individuals discussed hitting two U.S. targets.

As part of the investigation, authorities are checking passenger manifests from the crashed airplanes to see if they include anyone who attended flight schools in the United States or who used facilities that have airline simulators.

After an initial review of those manifests, investigators are looking at several people, including at least one with suspected links to bin Laden, a wealthy Saudi exile living in Afghanistan who is the accused mastermind of the 1998 bombings of two U.S. embassies in Africa.

Authorities, sources said, believe three to five hijackers were on board each of the four planes that crashed Tuesday. Two jets slammed into the towers of New York's World Trade Center, one hit the Pentagon, and the fourth crashed in rural Pennsylvania. Sources also said it's likely that at least one hijacker on each plane knew how to fly an aircraft.

Defense Secretary Donald Rumsfeld said the series of attacks represent a shift in the threats posed to the United States in the post-Cold War era.

"We are, in a sense, seeing the definition of a new battlefield in the world, a 21st century battlefield. It is a different kind of conflict," Rumsfeld said. "It is something that is not unique to this century to be sure, but given our geography and given our circumstance it is in a major sense new to this country.