A U.S. congressman, who is the target of a bribery investigation by federal authorities, says he intends to fight corruption allegations. A long-running federal probe into the activities of Louisiana Democrat William Jefferson led to an unprecedented search this past weekend of his congressional office.

Over the weekend, agents of the Federal Bureau of Investigation conducted an extensive search of Congressman Jefferson's Capitol Hill office.

Court documents made public just after the FBI raid say Jefferson accepted bribes to help a Kentucky-based technology company obtain contracts with U.S. government agencies, and with businesses and governments in West Africa.

The FBI investigation into Jefferson's activities involved a "sting" operation in which his contacts were secretly recorded, including a meeting last year outside a Virginia hotel at which he received a briefcase containing $100,000.

Later, an FBI raid on Congressman Jefferson's home recovered $90,000 in $100 bills stored in frozen food containers and wrapped in aluminum foil, money federal authorities say matched the cash given to Jefferson by a federal informer.

According to a lengthy court affidavit, the money was to have been used to pay off a middleman in a scheme to help Jefferson obtain contracts in Nigeria.

William Jefferson

In a news conference Monday on Capitol Hill, Jefferson repeated his contention that has done nothing wrong, but declined to comment further on specifics based on the advice of his attorneys:

"There are two sides to every story," said William Jefferson. "There are certainly two sides to this story. There will be an appropriate time and forum when that can be explained and explicated, but this is not the time, this is not the forum and operating on the advice of counsel I will not get into facts."

A former aide to Jefferson recently pleaded guilty to bribery charges, along with a businessman from the state of Kentucky.

The federal investigation into Jefferson raises significant concerns for minority Democrats who are relying on the issue of ethics as one weapon in their political arsenal leading to mid-term congressional elections this November.

House Democratic leaders have so far not publicly issued any call for Jefferson to resign his House seat, but there has been behind-the-scenes pressure for him to do so.

Ethics controversies have primarily put Majority Republicans in the spotlight. They include the bribery admission and conviction of Republican Congressman Randy Cunningham, links between the former House Majority leader Tom DeLay and former disgraced lobbyist Jack Abramoff, and another Republican lawmaker implicated in the Abramoff case.

However, the latest revelations about the federal probe into Jefferson make it easier for majority Republicans to throw the ethics issue back at Democrats.

The search of Jefferson's Capitol Hill office is the first time that has ever happened on Capitol Hill, and has provoked controversy, with some lawmakers asking questions about the authority of the FBI to carry out such a search.

Congressman Jefferson Monday questioned the authority with which the FBI searched his Capitol Hill office, calling it in his words, "an outrageous intrusion in the separation of powers between the executive and legislative branches of government."

The Jefferson matter also comes as lawmakers brace for continuing fallout from federal probes into alleged wrongdoing by members of Congress, and as a special House ethics committee, paralyzed by internal politics for 18 months, revives itself and prepares to carry out its own investigations.