RALEIGH, North Carolina (AP) -- A federal grand jury indicted two-time presidential candidate John Edwards on Friday over $925,000 spent to keep his mistress and their baby in hiding during the peak of his 2008 campaign for the White House.

The case of USA v. Johnny Reid Edwards contains six counts, including conspiracy, four counts of illegal campaign contributions and one count of false statements.

The indictment said the payments were a scheme to protect Edwards' White House ambitions. "A centerpiece of Edwards' candidacy was his public image as a devoted family man," the indictment said.

"Edwards knew that public revelation of the affair and the pregnancy would destroy his candidacy by, among other things, undermining Edwards' presentation of himself as a family man and by forcing his campaign to divert personnel and resources away from other campaign activities to respond to criticism and media scrutiny regarding the affair and pregnancy," the indictment added.

The indictment and an arrest warrant were filed in Greensboro, N.C., which is in the district where his campaign was headquartered.

Negotiations between Edwards' attorneys and federal prosecutors to settle on a charge to which Edwards was willing to plead guilty continued through Thursday, but proved fruitless, according to people with knowledge of the negotiations. Prosecutors had insisted on a plea to a felony, which would endanger his ability to keep his license to practice law.

An Edwards spokeswoman said she wasn't aware of the filing and declined immediate comment.

The indictment is the culmination of a federal investigation that lasted more than two years and scoured through virtually every corner of Edwards' political career. That included his political action committees, a nonprofit and a so-called 527 independent political group. It even examined whether he did anything improper during his time in the U.S. Senate, which ended seven years ago.

But the centerpiece of the investigation has long been the hundreds of thousands of dollars privately provided by two wealthy Edwards supporters - his former campaign finance chairman Fred Baron and Rachel "Bunny" Mellon, the 100-year-old widow of banking heir Paul Mellon. That money eventually went to keep mistress Rielle Hunter and her out-of-wedlock baby in hiding in 2007 and 2008, during the apex of the Democratic nomination campaign.

The indictment refers to $725,000 in payments made by Mellon and another $200,000 made by Baron. It said the money was used to pay for Hunter's living and medical expenses and for chartered airfare, luxury hotels and rental for a house in Santa Barbara, Calif., to keep her hidden from the public.

It accused Edwards of lying when he told the media he never knew about any payments.

Former campaign staffer Andrew Young, who initially claimed paternity of Hunter's child, has said Edwards was aware of the private financial support that helped keep the mistress satisfied and secluded. Prosecutors believe the private gifts should have been considered campaign contributions since they aided his candidacy.

The case opens a new front in how the federal government oversees the flow of money around political campaigns. An attorney for Edwards said last week that the government's case was "novel and untested" and argued that the government's theory was wrong on both the facts and the law.

With one of Edwards' former campaign rivals now sitting in the White House, the case includes a measure of political intrigue. Greg Craig, who was previously White House counsel for President Barack Obama, emerged as a leading figure on Edwards' legal team just as Obama's Justice Department was reviewing the case that prosecutors in North Carolina had prepared.

Meanwhile, North Carolina's two senators had asked to let Republican-appointed U.S. attorney George Holding stay on the job until he had finished the Edwards probe.

Edwards and Hunter began their relationship in 2006, just as the 2004 Democratic vice presidential nominee was plotting a second run for the White House. She was hired to shoot behind-the-scenes video footage of the prospective candidate. Edwards' political action committee and a nonprofit affiliated with him both paid Hunter's video-production firm about $100,000 for the work.

Edwards initially denied having an affair with Hunter but eventually admitted to it in the summer of 2008. He then denied being the father of her child before finally confessing last year. His wife, Elizabeth, died of cancer in December.

Young has said that Edwards agreed in 2007 to solicit money directly from Mellon. And the long-time Edwards aide, now estranged from his former boss, has said he received hundreds of thousands of dollars in checks from Mellon - some hidden in boxes of chocolate.

Mellon and Edwards are still friendly despite the glare of the federal investigation. They had lunch together at her Virginia estate last week even as the indictment appeared imminent.

Baron's support was even more direct. The wealthy trial lawyer said in 2008 that he helped Young and Hunter move across the country to protect them from media scrutiny. Baron, who died a few months later, said Edwards wasn't aware of the aid, but Young has said that Edwards did know.

Young, Hunter and Baron's wife were among many Edwards aides and supporters who were called to testify before a federal grand jury or have been interviewed by investigators.

Read the indictment: