WASHINGTON, May 8 (Xinhua) -- A former aide to U.S. Representative Bob Ney, a Republican from Ohio, pleaded guilty on Monday in the Jack Abramoff lobbying scandal and agreed to cooperation in the investigation.

    Neal Volz, Ney's former congressional chief of staff, pleaded guilty to conspiracy to corrupt Ney, other lawmakers and their aides, and to violation of the one-year ban on lobbying after leaving Ney's office in 2002.

    Volz admitted that he was involved in the conspiracy for more than four years, both as Ney's chief of staff and after leaving Ney's office to go to work for Abramoff.

    Ney has been a target of investigation by the Justice Department.

    In a statement, Ney's office insisted the lawmaker was "more confident than ever that he will be vindicated" in the investigation.

    In convicted, Volz faces up to five years in prison and a fine of 250,000 U.S. dollars. But he could receive a shorter jail term depending on his cooperation in the investigation.

    Previously, two former aides to Republican Representative Tom DeLay, from Texas, have pleaded guilty in the investigation of the lobbying scandal, which could implicate as many as 20 lawmakers. Enditem