Box cutters found on other September 11 flights

(CNN) -- The complex investigation into the terrorist attacks in New York and Washington gathered more strands of evidence over the weekend, leading authorities to several parts of the world.

The FBI says it's pursuing almost 150,000 tips and potential leads in its criminal investigation into the coordinated assault that destroyed the World Trade Center and severely damaged the Pentagon, killing thousands of people.

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A key part of solving the puzzle may be box-cutter knives or similar tools found on two flights made successfully, the same day that four United States commercial jets were hijacked and crashed, sources told CNN.

The hijackers who seized the airliners on September 11 had used box cutters to attack some of the crew and passengers, according to government officials and accounts from passengers in-flight who phoned relatives before their planes crashed.

A knowledgeable source said two small knives were found on a Delta flight that was supposed to depart Boston, and a box cutter was found on an Atlanta-to-Brussels Delta flight. These planes didn't take off since all flights were grounded after the hijackings. The tools were found when the planes were searched.

Investigators say they aren't sure whether the tools found were intended for some sort of innocent use or whether their owners may have had malicious intent. But they say the two planes' passenger manifests have been checked. And investigators increasingly believe that the weapons may have been prepositioned by accomplices for use by others. As one U.S. official told Time magazine, "These look like inside jobs."

Charles Miller, a U.S. Justice Department spokesman, told CNN some box cutters were found on other planes besides the four hijacked ones, but he did not provide any details.

Separately, two men who are now in federal custody were found with box cutters when they were detained in Texas two weeks ago. The men -- Ayub Ali Khan and Mohammed Jaweed Azmath -- had been on a flight from Newark, New Jersey to San Antonio, Texas that got diverted to St. Louis, Missouri. They were stopped on an Amtrak train on its way to San Antonio.

More evidence also has been revealed to explain a warning issued last week by the FBI to crop-duster plane owners and pilots telling them to be on the lookout for suspicious individuals.

Time magazine -- an AOL Time Warner sister medium to CNN.com -- reports that investigators found a crop-dusting manual during their search of a suspected terrorist hideout.

"We're right in the middle of our defoliation season of cotton in Georgia right now, and crop-dusters were grounded for about a week," said Rep. Saxby Chambliss. "Needless to say, they were upset, our farmers were upset, but there was a reason for it. And you're now seeing what the reason was."

Time does quote a senior official as saying they do not place "high credibility" on the notion that hijackers were exploring the idea of stealing or renting crop-dusters.

Detainees held

Hoping to further encourage forthcoming information, the reward money for the capture of the terrorists behind the September 11 attacks now has been set at $25 million by the U.S. State Department.

The reward money is part of a $5.1 billion spending package to deal with the costly aftermath, the first installment of a $40 billion emergency recovery package approved by Congress and President Bush.

Some of those wanted for questioning in the alleged terrorist conspiracy have been caught in the international dragnet.

A 29-year-old man arrested in west London in connection with the terrorist strikes on the World Trade Center was released Saturday, Scotland Yard said.

Two other men and one woman arrested Friday by anti-terrorist branch officers remained in custody.

The officers arrested two men and one woman in west London in 3 a.m. raids at two separate residences. Both residences also were searched.

A third man was arrested in the West Midlands region near Birmingham around 7 p.m., police said. The four were apparently questioned in a central London police station.

British police carried trash bags of evidence from the Birmingham address, and, for examination purposes, police also towed an expensive German car parked at the residence.

Of the first three arrested, a 27-year-old man and 25-year-old woman were living together at one residence. The 29-year-old man, now released, was picked up at another residence.

There were no details given on the arrest of the third man, who is in his mid-40s.

Authorities declined to explain how the suspects may have been linked to the September 11 hijackings of two jetliners that were crashed into the twin towers of the World Trade Center 18 minutes apart.

But a law enforcement source told The Associated Press that one of four people arrested in England on Friday took flying lessons at the same Arizona school, and at the same time, as a terrorist in the Pentagon attack. The individuals in custody had not been cooperating with authorities, the law enforcement source added.

No nationalities were given for those arrested.

Other European arrests

In France, eight people are being detained suspected of belonging to extremist groups thought to be planning attacks on U.S. interests in France, the interior ministry announced.

Counter-intelligence officers arrested the suspects on orders of magistrates probing threats made against U.S. interests, possibly including the U.S. Embassy in Paris. The probe had been opened the day before the attacks in the United States.

Police sources said the arrests came after an Algerian man, identified as Djamel Begal, allegedly confessed to planning an attack on the embassy while being held in the United Arab Emirates. He gave the names and addresses of extremists in Paris, the sources said.

At least one of the suspects apprehended in France had been in contact with Begal, and others had been under police surveillance since Begal's arrest in the UAE in July, sources said. Police are investigating possible links between the French case and two arrests last week in Brussels.

A prosecutor's office in Brussels said two men believed to have been planning an attack on American interests in Europe have been charged with possession of weapons of war. They were members of a radical group, said Fabienne Laduron, a spokeswoman for the prosecutors.

She said prosecutors were not ruling out a connection with Osama bin Laden, the Saudi exile identified by top U.S. officials as the prime suspect in the attacks.

Extradition sought

U.S. authorities are still seeking the extradition from Toronto of Nageeb Abdul Jabar Mohamed Al-Hadi. In a federal complaint filed in Chicago, he's charged with carrying false documents, including multiple Yemeni passports. The FBI said papers written in Arabic were found sewn in his clothing. Al-Hadi was flying from Germany to Chicago when his flight was diverted to Toronto on the day of the attacks.

Authorities also found two Lufthansa crew uniforms in his suitcases.

A court document says Al-Hadi is believed to be a Lufthansa employee, but it was unclear whether as a contract employee he had proper access to the uniforms in his luggage.

Al-Hadi was charged in federal court in Chicago with carrying false documents, but authorities did not immediately say what, if any, connection the man had with the hijackers. He was not in the Chicago courtroom as the charges were filed, as he is detained in Toronto.

The cockpit voice recorder recovered in the wreckage of United Flight 93, which crashed into a Pennsylvania field, has yielded evidence of a "definite struggle" in the cockpit. Officials familiar with the recording say shouts in English and Arabic and the sounds of a scuffle can be heard.

Several family members of passengers on the doomed jet previously described cell phone conversations indicating that passengers may have tried to retake control of the plane.

FBI Director Robert Mueller visited the crash site last week. Without going into details, Mueller seemed to confirm that the passengers attempted some type of takeover.

"I think ... both the attorney general and I -- and the attorney general of Pennsylvania -- have indicated we believe those passengers on this jet were absolute heroes and their actions during the flight were heroic," he said.

Other developments

-- The FBI now believes suspected hijacker Abdul Aziz Alomari -- one of the men officials say they think was aboard American Airlines Flight 11, which slammed into the north tower of the World Trade Center -- played a "key leadership role" in the attacks, law enforcement sources tell CNN.

-- In trying to establish a connection between the suspected terrorists' support operation and bin Laden, a source high in the investigation tells CNN that the emphasis is on tracking the money. It's a trail that may be made easier to follow by evidence that most of the funds seem to have been distributed through a single source.

-- A federal judge in Detroit, Michigan, denied bail Friday for three men arrested this week in connection with the attacks on the World Trade Center and the Pentagon.

-- Travel bookings Web sites Travelocity.com and Expedia.com confirmed with CNN on Friday that they have been approached by investigators to provide reservation data.

-- In northern Kentucky, six search warrants -- four federal and two state -- were executed as part of the investigation. Officials said "numerous" people were interviewed by FBI agents and 25 were detained on potential immigration violations.

-- CNN National Correspondent Mike Boettcher contributed to this report.