The FBI plans to interview every male page who may have worked on Capitol Hill during the 12 years that former Rep. Mark Foley served in the U.S. House of Representatives, FOX News confirmed Wednesday.

With scores of participants in the congressional program each year, that could amount to hundreds of interviews of former pages who worked on Capitol Hill as far back as January 1995.

Several male pages already have been interviewed, but the bureau now is going back to the beginning of the Foley-House timeline in search of earlier candidates.

Meanwhile, in the House, ethics committee members were hearing from former Foley chief of staff Elizabeth Nicolson, who followed Rep. Rodney Alexander, the congressman who sponsored the page whose e-mails with Foley forced the Florida Republican's resignation on Sept. 29.

Nicolson, who spent three and a half hours in the room, has told former associates that she was unaware of Foley's inappropriate contacts with ex-pages.

"She just honestly had no clue," said a former co-worker.

Wednesday was Alexander's second appearance this week before a specially-convened subcommittee of the House Committee on Standards of Official Conduct. He would not discuss the details of the testimony he gave, but said "it went good."

"We told them what we know, when we knew it and what we did about it," Alexander told reporters after three hours of testimony. The Louisiana Republican said that he was concerned that several people knew more and earlier about the inappropriate contacts.

Alexander says Foley's behavior came to his attention when the parents of the former page approached him about the e-mails in June 2005. He says his aides then contacted the office of House Speaker Dennis Hastert, R-Ill., for advice on what to do about the communications.

The ethics panel also is looking into at least two other incidents involving Foley and pages: a 2001 or 2002 episode involving e-mails to a former page and an incident several years ago in which Foley reportedly tried to gain access to the page dorm while intoxicated.

"It's quite apparent from some of the reports out there, that there are many people that know what we know, and have known for a longer period of time than we've known. There are people that know what the sexually explicit e-mails contained and have known about them for a longer period of time," he said.

While Hastert's staff has not denied being contacted by Alexander's aides, accounts of other top GOP lawmakers and their aides are at odds with the speaker's. House Majority Leader John Boehner, R-Ohio, has said he discussed the Foley situation with Hastert last spring after Alexander informed him of the e-mails. So has Rep. Tom Reynolds, R-N.Y.

Boehner is scheduled to testify Thursday, as is Jeff Trandahl, the former House clerk and day-to-day overseer of the page program until leaving Capitol Hill last year. Trandahl apparently confronted Foley about the e-mails and other alleged incidents, including a 2001 or 2002 episode in which the Florida congressman sent e-mails described as "creepy" to a former page sponsored by Rep. Jim Kolbe, R-Ariz. Kolbe's office went to Trandahl and the e-mails stopped.

Trandahl also could be in position to support testimony by Kirk Fordham, a former top aide to Foley, who told the ethics panel that he informed top House GOP aides of Foley's inappropriate behavior toward pages years ago. Fordham testified about an episode several years ago in which a drunk Foley is said to have tried to enter the page dorm. No police records have backed up the incident.

Those top House GOP aides include Scott Palmer, Hastert's longtime top aide and confidant, who denies Fordham's account and who is not mentioned in an account by the speaker's office regarding the 2005 incident with the Louisiana page. Hastert aide Palmer has yet to testify; neither has the speaker.

Alexander stressed that the parents of the page are hoping the ethics committee finishes the investigation quickly so the attention will be taken off their son.

"Hopefully, this will come to a conclusion and we can move onto other things, and no more young people will be put in harm's way," he added.

But even if the panel wraps up its work quickly, federal law enforcement officials say their intention is to make a thorough go of it, and are ready for a long slog through the interviews.

"You're talking about contacts he may have had prior to a widespread use of e-mail," one official said.

E-mail, the sources point out, was not as acceptable a form of immediate communication in the mid-1990s as it is today, and had yet to be adopted by many, including by the House of Representatives. The Foley trail is a bit easier to pick up starting in the late 1990s when online communications became common.

One of the law enforcement officials who spoke with FOX News said in a somewhat frustrated tone that one other obstacle in the investigation is that Foley appears to have been able to walk right up to the legal line, but did not cross it.

"That's why we still haven't been able to go in and get the computers. We don't have probable cause," the official said.

On Tuesday, House Sergeant-at-Arms Wilson Livingood, a member of the Page Board, which oversees the program for high school students who basically function as congressional interns, was questioned for less than two hours. He would not comment afterward.

Separately this week, Page Board members discussed a camping trip Kolbe took with two former pages and others to the Grand Canyon in 1996. The trip is under review by the Justice Department.

Kolbe, who is retiring at the end of this term, has repeatedly said that nothing inappropriate occurred on the trip, which the pages paid to attend.

He also told FOX News that he has not discussed the trip with anyone on the ethics panel.

"I haven't been contacted by anyone in this matter, but if I am, I will fully cooperate with the appropriate authorities."

FOX News' Ian McCaleb and Jim Mills and The Associated Press contributed to this report.