The FBI had information about potentially shady business deals involving a Louisiana congressman going back the late 1990s — at least eight years before he was indicted for taking bribes, an FBI agent testified Thursday.

FBI agent Timothy Thibault said during a pretrial hearing at U.S. District Court that he found a bureau document from the late 1990s questioning Rep. William Jefferson's business deals with a sugar company. It was not immediately clear what investigation, if any, occurred at the time.

Jefferson, a Democrat from New Orleans, was indicted earlier this year on charges including bribery, racketeering, money laundering and obstruction of justice.

The indictment spells out a dozen separate bribery schemes in which Jefferson allegedly used his influence as co-chairman of the congressional Africa Investment and Trade Caucus to broker deals in exchange for hundreds of thousands of dollars in bribes.

The current investigation began in March 2005, when a prominent northern Virginia businesswoman, Lori Mody, approached the FBI and complained that she was being swindled in a business deal involving Jefferson and some of his associates.

Thibault's testimony came in a pretrial hearing in which Jefferson's lawyers are seeking to suppress statements Jefferson made and some evidence taken from his New Orleans home in an August 2005 raid.

Jefferson had been expected to testify Thursday to support his lawyers' argument that Jefferson should have been advised of his right to remain silent before the interview occurred.

But Thursday's hearing ran long and was continued until Jan. 16. Jefferson's lawyer, Robert Trout, has said he plans to call Jefferson as a witness, but he is not obliged to do so.

The congressman made potentially damaging statements at the end of the interview, after seeing a surveillance videotape in which he was retrieving a suitcase filled with $100,000 cash. Jefferson dejectedly told the agents "what a waste," and speculated about his political future, according to the agents' testimony.