A federal grand jury has indicted the chairman of the Republican Party of North Carolina in an alleged bribery scheme, accusing him of helping a wealthy political donor try to influence a state regulator whose department has oversight of the donor’s company.

Federal prosecutors said Tuesday that the chairman, Robin Hayes, who is also a former U.S. congressman, and three other people plotted to funnel campaign contributions to Mike Causey, the commissioner of the North Carolina Department of Insurance, in exchange for him taking actions that would benefit donor Greg Lindberg’s company.

In addition, the indictment said Lindberg’s associates spoke to a person described as “public official A” about helping with the state insurance department. “Public official A” then allegedly called Causey to put in a good word about Lindberg, the indictment said. Lindberg promised to donate $150,000 to ”public official A’s” political committee., authorities said

Several days later, Lindberg made a contribution of that amount to Rep. Mark Walker (R-N.C.). A spokesman for Walker coud not confirm whether Walker was public official A, but said that Walker has been cooperating with the Department of Justice.

“Walker is not and never has been a target of this investigation, and has committed no wrongdoing,” Jack Minor, Walker’s communications director said.

Causey is not charged in the case. By January 2018, prosecutors say, Causey became suspicious and alerted federal law enforcement, then participated in the investigation.

Hayes’s attorney Kearns Davis said Hayes “steadfastly denies” the allegations. “We look forward to a swift conclusion to this matter, and to clearing his name,” Davis said.

Lindberg’s lawyer Anne Tompkins said her client “is innocent of the charges in the indictment and we look forward to demonstrating this when we get our day in court.”

The indictment, which was handed down March 18 and announced Tuesday, said Lindberg mainly wanted the senior deputy commissioner at department sidelined and at one time pressed to have one of his own associates, John Palermo Jr., installed in a government role where the senior deputy wouldn’t “breathe a word outside that office, or send a slip of paper outside that office, that is not reviewed first by John [Palermo].”

That idea was later nixed for fear it would be too transparent that Causey hired someone from Lindberg’s company, federal authorities said. Lindberg, who owns Global Bankers Insurance Group, later pushed to have the senior deputy moved to a different job, telling the commissioner that his deputy was “deliberately and intentionally and maliciously hurting my reputation with other regulators,” the indictment said.

Hayes, Lindberg, and Lindberg’s associates, John Palmero and John Gray, were indicted on conspiracy and bribery charges amid an ongoing investigation into Lindberg’s political donations.

“These men crossed the line from fundraising to felonies when they devised a plan to use their connections to a political party to attempt to influence the operations and policies of the North Carolina Department of Insurance,” said John Strong, the FBI Special Agent in Charge in Charlotte, N.C. “The FBI will root out any and all forms of public corruption. We remain committed to ensuring those who violate the public’s sacred trust are held accountable.”

According to prosecutors, Hayes sent a text message to Palmero in November 2017 suggesting that Lindberg make a contribution to the state party, and then Hayes would be able to funnel it wherever Lindberg wanted. Authorities said it was a way for Lindberg to circumvent the cap on how much an individual can donate to a candidate — and by using the state party as a pass-through entity, Lindberg could keep his name out of the mix.

In all, prosecutors said, Lindberg put $2 million toward his effort to support Causey’s -election, including $500,000 he donated to the North Carolina GOP state party. At one point, Lindberg wanted to move half of that to Causey’s coffers in one chunk. Lindberg and his associates called Hayes, who was reluctant to give that much money at one time for fear of drawing attention, but ultimately said, “whatever you all want to do, we’ll do,” the indictment said.

Hayes also allegedly lied to the FBI, telling agents Lindberg had never directed where his money should go or tied any ultimatum to his contributions. He also denied ever talking to Causey specifically about Lindberg, which he had on numerous occasions.

Hayes served in Congress for a decade before losing his seat in 2008.