The recipient, Clarence Prevost, was honored Thursday at a closed-door ceremony at the State Department, although the payout was secretly authorized last fall by Secretary of State Condoleezza Rice and the Justice Department, U.S. officials told The Associated Press.
The reward from the State Department's "Rewards for Justice" program is the first and only one to date to a U.S. citizen related to the Sept. 11, 2001, terrorist attacks, the officials said.
It is also unusual because Moussaoui, who was imprisoned at the time of the attacks, was never named as a wanted suspect by the program. The program mainly seeks information about perpetrators or planners of terrorist acts against U.S. interests and citizens abroad.
The State Department would not identify the recipient, citing privacy and security concerns.
Two administration officials, however, said the reward went to Prevost, a key witness at Moussaoui's trial who has previously spoken out about his involvement in the case. The officials spoke on condition of anonymity because they were not authorized to speak publicly about the matter.
Prevost, 69, is a former Navy pilot who later flew for Northwest Airlines and goes by his nickname "Clancy." He was Moussaoui's flight instructor at the Pan Am International Flight Academy outside Minneapolis.
No one answered at an apartment listed for Clarence Prevost in a residential hotel in Coral Gables, Fla., an upscale Miami suburb. Calls to a number listed to Prevost were not answered.
None of the immediate neighbors who were home Thursday evening recognized his name, but a hotel concierge who declined to give his name said he sometimes chatted with the Minnesota flight instructor. The concierge described him as tall, thin, and unassuming and said he never had mentioned any involvement with the Moussaoui case.
He was one of several people who worked at the flight school that Moussaoui attended in August 2001 and who alerted the FBI to his suspicious desire to pilot jumbo jets.
News of the reward came as a surprise to two other Pan Am flight instructors, Tim Nelson and Hugh Sims, who also have been credited with tipping the FBI to Moussaoui and were honored by the Senate in 2005 with a resolution that commended their "bravery" and "heroism."
Sims, in a phone interview from Fort Myers, Fla., said he didn't want to comment "till we get a few things straightened out."
"He was certainly there but he didn't call the FBI. I have no idea why he received the reward," Sims said.
Prevost said during the trial that he urged flight school officials to call the FBI and one day an agent showed up to ask him questions about Moussaoui.
Sims recounted meeting Moussaoui at Pan Am on a Monday, and said that two days later he and Nelson each called the FBI separately.
"Clancy had a part of it. Whether he continued to expand on his portion of this, that's fine," Sims said. "Today has been a very large surprise for me."
Nelson was talking with family members Thursday evening and was not immediately available, his wife, Jodie Quinn-Nelson said. She said the reward "was given out to the wrong person" and said her husband was upset.
"We're just kind of dumbfounded with what happened here," she said.
Prevost and the others said they thought it was strange Moussaoui wanted to learn to fly a Boeing 747 despite the fact that he had little flying background.
After his arrest, Moussaoui sat in jail for 3 1/2 weeks on an immigration violation, saying little to investigators before hijacked planes slammed into the World Trade Center and the Pentagon or crashed in a Pennsylvania field on Sept. 11.
The Minneapolis FBI agents who responded to the tips were unable to persuade their superiors in Washington to seek a national security warrant to search Moussaoui's belongings and laptop computer.
Moussaoui later confessed to being the "20th hijacker" and was sentenced to life in prison without parole in 2006 after a trial marked by numerous outbursts, conflicts with his lawyers and questions about his status, if any, within Osama bin Laden's al-Qaida network.
He told jurors he was to have piloted a fifth plane on Sept. 11 and fly it into the White House.
But after the jury decided against sentencing him to death, Moussaoui recanted his testimony and denied any role in 9/11, saying he lied on the stand because he assumed he had no chance of getting a fair trial.
Rewards for Justice, which was created in 1984, has paid about $77 million in rewards to more than 50 people.
By MATTHEW LEE and LARA JAKES JORDAN
Associated Press Writers