WASHINGTON -- In a burst of activity that ended 16 months of political gridlock, the House ethics committee Wednesday launched a flurry of investigations -- focusing on a Republican linked to convicted lobbyist Jack Abramoff and a Democrat at the center of a separate bribery probe.

The bribery investigations of Reps. Bob Ney, R-Ohio, and William Jefferson, D-La., will determine whether they violated House rules, but the probes only add to their legal woes. The Justice Department already is conducting bribery investigations of Ney and Jefferson, both of whom have denied wrongdoing.

By targeting a member of each party, committee leaders avoided allegations of partisanship in a year when Democrats are trying to make Republican misconduct a major campaign issue. Despite the inclusion of Jefferson, House Democratic leader Nancy Pelosi called the announcement "long overdue."

The investigations disclosed by the Republican ethics chairman and the senior Democrat on the evenly divided committee were only two of four separate announcements.

The committee leaders also approved an inquiry into whether other lawmakers were involved in a bribery scandal that landed former Rep. Randy "Duke" Cunningham, R-Calif., in prison with an eight-year sentence. And they said they would have investigated payments of former Majority Leader Tom DeLay's overseas travel -- had he not decided to leave Congress next month.

Ney's former top aide pleaded guilty last week to conspiring to corrupt the congressman on behalf of Abramoff and his clients. Two businessmen have pleaded guilty to bribing Jefferson to promote a company's operations in Africa.

Ney said he welcomed the investigation.

"For the last 15 months, all I have asked for is an opportunity to have the facts surrounding the Abramoff matter to be reviewed by the appropriate investigative bodies in order to have this matter addressed once and for all," Ney said in a statement.

He has stepped aside as chairman of the House Administration Committee because of the investigation by the Justice Department.

Jefferson's office had no immediate comment; the lawmaker has previously denied wrongdoing.

The committee of five Republicans and five Democrats had been in a partisan deadlock since the beginning of last year. The House GOP leadership removed two GOP members of the committee and the Republican chairman after they had admonished DeLay for his conduct. Since then, the committee has fought over committee rules and staffing, and failed to get a sixth vote to begin any investigation.

In April, the committee's top Democrat, Rep. Alan Mollohan of West Virginia, stepped down from the committee after published reports questioned his role in steering federal money to nonprofit group led by his supporters. Mollohan had feuded constantly with the current chairman, Rep. Doc Hastings, R-Wash.

Replacing Mollohan was Rep. Howard Berman, D-Calif., who earlier was the committee's top Democrat. Berman had good relations with Republicans on the panel.

Ney's former top aide, Neil Volz, admitted he conspired to corrupt Ney, his staff and other members of Congress with trips, free tickets, meals, jobs for relatives and fundraising events.

Volz said he engaged in a conspiracy, the intent of which was "to influence members of Congress in violation of the law." He enumerated 16 actions he said his old boss took on behalf of Abramoff clients.

In addition, Volz wrote, Abramoff gave the congressman and his staff numerous tickets to concerts and sporting events in the Washington, D.C., area; regular meals and drinks at restaurants including Abramoff's restaurant Signatures and unreported use of Abramoff's box suites at the MCI Center Arena in Washington and Camden Yards Stadium in Baltimore for political fundraisers for Ney and for candidates and political organizations he supported.

As for Jefferson, a Louisville, Ky., man pleaded guilty in federal court this month to bribing the congressman with more than $400,000 in payments, company stock and a share of the profits to promote a Kentucky company's high-tech business ventures in Africa.

Vernon L. Jackson was the second person to plead guilty to charges of bribing the eight-term Democrat to promote iGate's Inc.'s broadband technology -- in Nigeria, Ghana and Cameroon.

Hastings and Berman said investigators will look at allegations that Ney received gifts, travel benefits, campaign contributions and other items of value from Abramoff and his associates -- and the relationship of any favors to Ney's legislative actions.

They said the Jefferson investigation will focus on whether the lawmaker or his family got cash, stock shares, agreements for future profits or other benefits from several individuals or iGate Inc. -- and how any such favors affected his legislative actions.