A tipster who helped the FBI catch Sept. 11, 2001 terror attack conspirator Zacarias Moussaoui has finally received a $100,000 reward, while another man credited as a tipster still has received nothing.

Tim Nelson said Wednesday he collected the reward at the Minneapolis FBI office last week. He said he was satisfied to finally get the recognition, but he believes the $5 million reward that went to a colleague last year was "exorbitant" and that the government's procedures for handing them out are too secretive.

Nelson was an instructor at the Pan Am International Flight Academy who called the FBI about a month before the Sept. 11, 2001, attacks to report his suspicions about Moussaoui, who had showed up at the Eagan flight school with thousands of dollars in cash and asked for training on Boeing 747 simulators.

Another former instructor who independently made a separate call to the FBI that day said Wednesday that he still has received nothing.

"I'm kind of flabbergasted by the whole thing," said Hugh Sims. "I don't know where we're going to go from here."

The U.S. Senate approved a resolution in 2005 commending Nelson and Sims for their bravery and heroism in alerting the FBI.

Another instructor at the school, Clarence Prevost, received a $5 million reward in January 2008 through the State Department's Rewards for Justice program, which says it has paid more than $77 million to more than 50 people who provided information that led to the arrests of terrorists or prevented terrorist attacks.

Prevost was a key witness in Moussaoui's 2006 trial, which ended with Moussaoui, a French citizen, being sentenced to life in prison without parole. Prevost testified that he urged his bosses at the school to call the FBI.

Members of the state's congressional delegation questioned why Prevost was rewarded when Nelson and Sims weren't.

Nelson and Sims said Prevost didn't call the FBI himself, like they did.

Nelson said that during the Dec. 2 reward presentation, his wife, Jodie Quinn-Nelson, asked what Prevost had done to deserve $5 million. He said Agent Harry Samit, who arrested Moussaoui, replied that Prevost had testified.

Sims said he'd understand if the FBI had no record of what he and Nelson had done. But he said he called the FBI on Monday "because I kind of got my feelings hurt" and was able to reach the agent to whom he originally gave his tip. He said the agent still remembered their conversation.

Nelson said their names are included in FBI documents that Moussaoui's lawyers introduced during his trial.

Nelson said he asked the inspectors general of both the Justice Department and State Department this week to investigate how the rewards were vetted and whether Prevost exaggerated his role. He said he was told his reward required approval from Secretary of State Hillary Rodham Clinton.

Prevost declined to comment Wednesday. A spokesman for the Minneapolis FBI office, E.K. Wilson, did not immediately return a phone call seeking comment Wednesday. Neither did officials with the Rewards for Justice program.