"It is our responsibility to protect player safety and the integrity of our game, and this type of conduct will not be tolerated," Goodell said in a statement. "We have made significant progress in changing the culture with respect to player safety and we are not going to relent. We have more work to do and we will do it."

The NFLPA issued a statement Friday, stating it would review the findings.

"Health and safety is a paramount issue to the NFLPA," the statement read. "The NFLPA was informed of this investigation by the NFL earlier today and will review the information contained in the league's report."

Goodell has advised the Saints that he will hold proceedings to determine potential discipline against the team and the individuals involved, and confer with the players' union regarding the appropriate punishment. That discipline could include fines, suspensions and the forfeiture of draft choices.

"I have been made aware of the NFL's findings relative to the 'Bounty Rule' and how it relates to our club. I have offered and the NFL has received our full cooperation in their investigation," Benson said in a statement. "While the findings may be troubling, we look forward to putting this behind us and winning more championships in the future for our fans."

Rita Benson LeBlanc, Tom Benson's granddaughter and team co-owner/executive vice president, twice declined to comment on the situation when asked by ESPN.com on Saturday at the MIT Sloan Sports Analytics Conference in Boston. Benson LeBlanc was not asked about the bounty system during her panel discussion at the conference.

According to the investigation, the players regularly contributed cash into a pool and received improper cash payments of two kinds from the pool, based on their play in the previous week's game.

Williams administered the program with the knowledge of other defensive coaches and occasionally contributed funds, according to the league investigation.

Payments were made for plays such as interceptions and fumble recoveries. But the program also included "bounty" payments for "cart-offs," meaning that the opposing player was carried off the field, and "knockouts," meaning that the opposing player was not able to return.

"The payments here are particularly troubling because they involved not just payments for 'performance,' but also for injuring opposing players," Goodell said in a statement. "The bounty rule promotes two key elements of NFL football: player safety and competitive integrity."

A team source familiar with the investigation told SI.com that Saints linebacker Jonathan Vilma offered $10,000 to any defensive player that knocked Favre out of the 2009 NFC Championship Game.

Favre, who absorbed multiple hard hits in the game, told SI.com: "I'm not pissed. It's football. I don't think anything less of those guys."

Favre's agent, Bus Cook, said he was unaware of the investigation until Friday. He said the Saints should have been penalized for several hard, late hits during the 2009 NFC Championship Game and that he believed the contact was not coincidental.

"It was pretty obvious that the intent was to take Brett out of the game, and it happened the week before with Kurt Warner, too," Cook said. "I don't know anything about whether it was by design or whatever, but I think a lot of people shared that same viewpoint that there were some hits that didn't get called."

Cook, however, said Favre never suggested to him he was maliciously targeted.

"That's part of football, getting hit," Cook said. "Brett never complained to me one way or another."

The NFL has a longstanding rule prohibiting "non-contract bonuses," and they violate both the league constitution and bylaws and the collective bargaining agreement with the players' union. Clubs are advised every year of this rule in a memo from the commissioner.

"Our investigation began in early 2010 when allegations were first made that Saints players had targeted opposing

players, including Kurt Warner of the Cardinals and Brett Favre of the Vikings," Goodell said in a statement. "Our security department interviewed numerous players and other individuals.

"At the time, those interviewed denied that any such program existed and the player that made the allegation retracted his earlier assertions. As a result, the allegations could not be proven," Goodell said.

"We recently received significant and credible new information and the investigation was re-opened during the latter part of the 2011 season."

Warner, who retired after the 2009 season, responded to a fan's comment on Twitter that even if the Saints had a bounty program a playoff hit on Warner was clean. Warner tweeted, "I would have to agree with you!!!"

"I don't want to say that there was an attempt to injure, but I definitely think there were games where I could tell you that it seemed that they went beyond what was normal in regard to when they were going to hit me or how they were going to hit me," Warner said on the NFL Network. "Again, not with the intention necessarily of hurting me, but knocking me out of my game to get me to think about things differently. If by chance they hit me and knocked me out of the game, maybe that's a benefit for them."

Chicago Bears wide receiver Earl Bennett was injured by a hit from Roman Harper, who was not flagged or fined, in a Week 2 loss to the Saints. Bennett missed five weeks with a chest injury.

"All I have to say is I hope we play them again," Bennett told ESPNChicago.com Friday. "The game of football is a contact sport, so if they're gunning for me, I'm going to be gunning for them."

Williams employed a similar system while with the Redskins from 2004-07, according to a report Friday in The Washington Post.

Three former players said Williams handed out thousands of dollars in accordance with a specific scoring system, including "kill shots" that resulted in opposing teams' top players being knocked out of the game.

Daniels, however, went on the record in the Post report and defended Williams.

"I think it is wrong the way they're trying to paint (Williams)," Daniels told the Post. "He never told us to go out there and break a guy's neck or break a guy's leg. It was all in the context of a good, hard football."

Daniels told the Post it was his understanding that Williams started the "bounty" program with money collected from fines for players being late for practices and meetings.

"Rather than pocket that money or whatever, he would re-distribute it to players who had good games or good practices," Daniels told the Post.

Daniels told the Post the most money he ever received was $1,500 for a four-sack game against the Cowboys in 2005.

According to the NFL investigation of the Saints, Benson was not initially aware of the bounty program and directed Loomis to make sure it was discontinued immediately. The evidence showed Loomis did not do so, investigators found.

"Similarly, when the initial allegations were discussed with Mr. Loomis in 2010, he denied any knowledge of a bounty program and pledged that he would ensure that no such program was in place. There is no evidence that Mr. Loomis took any effective action to stop these practices," according to the league's findings.

Payton "was not a direct participant in the funding or administration of the program," according to the investigation.

However, Payton "was aware of the allegations, did not make any detailed inquiry or otherwise seek to learn the facts, and failed to stop the bounty program. He never instructed his assistant coaches or players that a bounty program was improper and could not continue," the investigation found.

The investigation included the review of approximately 18,000 documents totaling more than 50,000 pages, interviews of

a wide range of individuals and the use of outside forensic experts to verify the authenticity of key documents.

A memo sent by the NFL to all 32 teams detailing the investigation was obtained by CBS Sports, which reported that Michael Ornstein, a former marketing agent with close ties to Payton and former Saint Reggie Bush, contributed to the bounty fund.

Ornstein, who served time in prison for fraud, pledged $10,000 to the quarterback bounty in 2009, and contributed money at least twice in 2011, according to CBS Sports.

According to CBS Sports, the memo also details an email sent from Ornstein to Payton, which outlined the bounty system.

The NFL's most infamous bounty case occurred in 1989 when Eagles coach Buddy Ryan was accused of putting a bounty on Cowboys players.

On Thanksgiving Day, Cowboys coach Jimmy Johnson accused Ryan of putting a bounty on Dallas quarterback Troy Aikman and placekicker Luis Zendejas before a 27-0 Philadelphia victory. Ryan and his players denied the charges and NFL commissioner Paul Tagliabue found no evidence of wrongdoing.

Information from ESPN NFL Insider Adam Schefter, ESPNChicago.com and The Associated Press was used in this report.