U.S. law-enforcement authorities knew as early as 1995 that Middle Eastern men were training at American flight schools and had discussed crashing planes into federal buildings, but did not follow up on the information, according to documents and interviews with American and Filipino authorities.
The information came to light during Filipino police questioning of Ramzi Yousef and Abdul Hakin Murad, the two men arrested in 1995 after a chemical fire at a Manila apartment accidentally revealed a major terror plot with ties to Usama bin Laden.
Murad and Yousef, who also had ties to the New Jersey-based group of terrorists who bombed the World Trade Center in 1993, are serving life sentences in the United States for an elaborate plot to blow up a dozen U.S. trans-Pacific airliners in one day.
But secret Filipino records, as well as police and intelligence personnel in that country who spoke to the Associated Press, indicate that Murad's intentions were even grander.
"Murad's idea is that he will board any American commercial aircraft pretending to be an ordinary passenger, then he will hijack said aircraft, control its cockpit and dive it at the CIA headquarters," one Filipino police report from 1995 said.
"There will be no bomb or any explosive that he will use in its execution. It is a suicidal mission that he is very much willing to execute," it continued.
The Filipino authorities said that they gave the information immediately to the FBI office in Manila, but that the Americans disregarded the hijacking plans to focus on the better-developed and more immediately threatening airliner-bombing plot.
"We shared that with the FBI," said Robert Delfin, chief of intelligence command for the Philippine National Police. "They may have mislooked (sic) and didn't appreciate the info coming from the Philippine police."
FBI and other American law-enforcement officials, who spoke only on condition of anonymity, said that they considered Murad's suicide hijacking idea was half-baked, and in any case involved taking control of only a small single-engine plane that could not do much damage.
Murad, who later claimed he was tortured during his interrogations, also told Filipino authorities how he and a Pakistani friend had crisscrossed the United States, attending flight schools in New York, Texas, California and North Carolina on his way to earning a commercial pilot's license.
He identified to Filipino police approximately 10 other Middle Eastern men who met him at the flight schools or were getting similar training.
One was a Middle Eastern flight instructor who came to the United States for more training; another a former soldier in the United Arab Emirates. Others came from Sudan, Saudi Arabia and Pakistan.
None of the pilots match the names of the 19 hijackers from Sept. 11.
The U.S. officials said the FBI interviewed people at the flight schools named by Filipino police, but did not find evidence that any Middle Easterners other than Murad were plotting anything. With no other evidence to go on, they took no further action, the officials said.
FBI agents descended upon the flying schools in 1995, and returned to some of those locations immediately after Sept. 11.
"There were several of them [Middle Eastern pilot students] here. At one point three or four were here," said Laura Flynn, an assistant manager at Richmore Flight School in Schenectady, N.Y., where Murad and a friend attended in the mid-1990s.
"Supposedly they didn't know each other before, they just happened to show up here at the same time. But they all obviously knew each other," she said.
Flynn said FBI agents mentioned Murad was suspected in a bombing plot but did not say anything about a suicide hijacking. She said agents returned to the school after Sept. 11 "and asked about any of the foreign people, pulled some records."
The Filipino police investigation also uncovered links between Murad and Yousef and a Muslim cleric from Malaysia who has emerged in the past few months as a key figure in the investigation of last year's suicide hijackings.
Authorities in Malaysia have said they believe the cleric, who goes by the name Hambali, met with two of the Sept. 11 hijackers in 2000 and may be a central figure in terrorist groups with links to bin Laden that have emerged in southeast Asia. Authorities are seeking Hambali's arrest.
Delfin, the Filipino police intelligence officer, said when he saw the Sept. 11 attacks on television, Murad's disclosures immediately came to mind.
"This is it, this was what Murad was saying," Delfin said he remarked to other intelligence officials.
Rodolfo Mendoza, the former police intelligence official who oversaw Murad's interrogations, had the same reaction.
"It's exactly as what Murad said before, 'I will hijack a commercial plane and dive crash it,'" he said.
Murad told authorities he discussed the suicide hijacking idea with Yousef just a few months before their arrest and had not yet developed a specific plan, although they discussed targets like the CIA building and the Pentagon in the Virginia suburbs of Washington. The Pentagon was struck Sept. 11.
"I am telling you that I told Basit [Yousef] that there is a planning, what about we dive to CIA building," Murad is quoted in one transcript as telling police interrogators. "He told me OK, we will think about it."
Filipino police questioned his willingness to die. "You are willing to die for Allah or for Islamic [sic]?," one asked.
"Yes," Murad replied.
"Really?" the interrogator asked.
Later Murad offered some insight. "All my thinking was," he said, "that I should fight the Americans. I should do something to show them that we are, we could stay in their face."
— The Associated Press contributed to this report.