Mr. Rauf's involvement was another flashpoint between American and British officials investigating the plot.
The teacher then went to the police, who were already investigating the plot based on another tip from a student.
The organizer, James Tobin, of Bangor, Me., had been accused of making false statements to F.B.I. agents investigating the plot.
Federal, state and local authorities investigated the plot for eight months as the three stockpiled guns and explosives in preparation for bombing an apartment complex where 120 people lived including the Somalians, according to the charges.
That scenario would mark a dramatic revision of the commonly understood narrative of the Sept. 11 attacks and contrasts sharply with prevailing theories of FBI agents investigating the plot.
County sheriff Jim Mele told reporters that while investigating the plot, police had found a list of victims that the pupils intended to target during the shooting at Summerville High School in Tuolumne, California.
The Saudi government has vigorously denied that it had any part in the Sept. 11 attacks, and the commission investigating the plot found "no evidence that the Saudi government as an institution or senior Saudi officials individually funded" Al Qaeda, the terror group that carried out the attacks.
Shapiro is doubtful that the FBI has truthfully acknowledged the records relevant to his requests, and wonders whether the Bureau investigated the plot to assassinate US citizens on domestic soil for exercising their First Amendment rights.
The Interior Ministry said it was still investigating the plot surrounding the bombing, but described a suspected accomplice arrested earlier as involved in "deviant ideology" — a term generally used to characterize Islamist militancy.
Judge Sotomayor said the Federal Bureau of Prisons had said it needed two weeks to investigate the murder plot while keeping Mr. Gotti isolated.
