(CNN) Federal prosecutors have unsealed an indictment charging North Carolina State Republican Party Chairman Robin Hayes and three associates in an alleged bribery scheme involving campaign contributions to the state insurance commissioner.
Hayes, along with political and business figures Greg Lindberg, John Gray and John Palermo, made initial appearances in US District Court in Charlotte Tuesday.
"The indictment unsealed today outlines a brazen bribery scheme in which Greg Lindberg and his co-conspirators allegedly offered hundreds of thousands of dollars in campaign contributions in exchange for official action that would benefit Lindberg's business interests," Brian Benczkowski, the assistant attorney general of the Justice Department's criminal division, said in a news release.
The March 18 indictment charges Hayes, Lindberg, Gray and Palermo with wire fraud as well as bribery concerning programs receiving federal funds and aiding and abetting. Hayes also has been charged with making false statements. CNN has reached out to their attorneys.
Hayes "steadfastly denies the allegations made against him in this case,"said Kearns Davis, his attorney.
"After a long and distinguished career in public service at the local, state, and federal levels, Robin volunteered his time helping to support the party and candidates for office in North Carolina. We look forward to a swift conclusion to this matter, and to clearing his name," Davis said in a statement Tuesday.
Anne Tompkins, an attorney for Lindberg, said he maintains his innocence.
"Greg Lindberg is innocent of the charges in the indictment and we look forward to demonstrating this when we get our day in court," Tompkins said.
The alleged scheme was to pay the commissioner of the North Carolina Department of Insurance at least $1.5 million in exchange for making staff changes, among other things, the court documents say.
The indictment comes in a year that has rocked the state's Republican Party. Last month, the North Carolina State Board of Elections set a new election in the 9th Congressional District race, having found widespread ballot fraud on behalf of Republican candidate Mark Harris. Earlier this week, Hayes announced that he would not seek re-election to run the state party.
In a statement released Tuesday afternoon, Josh Howard -- the counsel to the North Carolina Republican Party -- said the group is cooperating with investigators.
"Early this morning, the North Carolina Republican Party was made aware of several indictments surrounding the conduct of a major donor to both major political parties and two of his associates," Howard said. "The Party has been cooperating with the investigation for several months, including staff members providing statements and responding to various document requests. The Party, which has its day to day operations managed by professional staff under the direction of the NCGOP Central Committee, remains fully operational and focused on its mission at hand."