WASHINGTON (AP) _ The FBI's espionage case against a Los Alamos weapons scientist was ``flawed from the outset'' because authorities identified a number of other suspects, but failed to investigate them, a congressional report revealed today.

The report also disclosed for the first time that in a polygraph test in February when the scientist, Wen Ho Lee, was asked if he had passed nuclear secrets ``to any unauthorized person,'' he failed the test.

The report by the leaders of the Senate Governmental Affairs Committee outlined a string of missteps, communications lapses and misunderstandings over three years that prevented the FBI from establishing a strong case against the Taiwan-born scientist.

The findings summarized information gathered during two closed-door hearings the committee held on the federal investigation into Lee. He was fired from his top-secret job last March after being the primary suspect since 1996 in the alleged theft by China of secrets involving the sophisticated W-88 nuclear warhead in the 1980s.

Lee has not been charged with a crime, although a federal grand jury was hearing evidence in the ongoing case. In his only public comments, Lee in a television interview last Sunday categorically denied providing nuclear secrets to China or anyone else.

But the Senate report disclosed that last February, Lee was asked during an FBI polygraph test whether he had every given specific classified computer code related to weapons testing, or ``passed W-88 information to any authorized person?''

``Wen Ho Lee failed this polygraph test,'' said the report.

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