A former director of the Federal Bureau of Investigation, Robert Mueller III, will lead a probe into the National Football League's handling of former Baltimore Ravens player Ray Rice's domestic violence case, the league said on Wednesday.

The announcement comes within hours of a report by The Associated Press that a law enforcement official sent a video to the league in April that showed Rice knocking out his then-fiancee in an elevator.

The official wanted the NFL to have the video before deciding how to punish Rice, the agency said, adding that the official spoke on condition of anonymity.

The NFL has steadfastly insisted it had not seen the video until it went viral on Monday.

"We have no knowledge of this. We are not aware of anyone in our office who possessed or saw the video before it was made public on Monday," Greg Aiello, a spokesman for the National Football League, told Reuters earlier on Wednesday. Even so, he added, "We will look into it."

Mueller's probe will be overseen by NFL owners John Mara of the New York Giants and Art Rooney of the Pittsburgh Steelers, both of whom are attorneys, the league said in a statement.

NFL Commissioner Roger Goodell said Mueller would have access to league records and personnel and the final report would be made public.

The NFL suspended Rice indefinitely after the release of the video, taken in an elevator in a New Jersey casino, saying the clip showed the violence involved in the incident. Rice's team, the Baltimore Ravens, also cut the three-time Pro Bowler.

Weeks earlier, Goodell suspended Rice for just two games, based on another video from a camera outside the elevator that showed him dragging an unconscious Janay Palmer, whom he later married.

Critics of the league's handling of the incident contend that Goodell was too lenient in his initial punishment. Since the release of the new video, questions have surfaced over why the NFL was not able to obtain the clip before TMZ, the website that first aired it on Monday.

"If Goodell did see the video, which he says he didn't, then he should be fired," Washington Post columnist John Feinstein told Reuters. "If he didn't see the video, then he probably should be fired too - because he should have seen the video.

"He's guilty and everybody working around him is guilty, for giving him terrible advice," Feinstein said.

Goodell serves at the behest of the NFL team owners, and there is no sign they have lost confidence in him. At least two, Robert Kraft of the New England Patriots and John Mara of the New York Giants, have voiced support for Goodell since Monday.

GOODELL: JOB NOT IN JEOPARDY

In a "CBS This Morning" interview that aired earlier on Wednesday, Goodell said he did not believe his job was on the line over his handling of the case, which has rekindled a national discussion over domestic abuse.

But Goodell, who has a reputation for being tough on players who break the rules, has conceded he didn't get it right by suspending Rice for just two games, and he later spelled out tougher policies for players involved in domestic abuse.

"People expect a lot from the NFL," he said, adding that he was still learning about domestic abuse.

"We accept that," Goodell said of the league's responsibility. "We embrace that. That's our opportunity to make a difference, not just in the NFL, but in society in general."

The 55-year-old Goodell, who has been the NFL commissioner since 2006, has said he tried and failed to obtain the video from inside the elevator.

"On multiple occasions we asked for it," Goodell said. "And on multiple occasions we were told 'no.' I understand that there may be legal restrictions on them sharing that with us."

When told many people do not believe that, Goodell said, "It's a fact."

Rice, 27, was indicted by a grand jury in March on third-degree aggravated assault, but the charge was dropped because Palmer declined to testify against him. He ultimately agreed to court-supervised counseling as part of a pre-trial intervention program.

Mueller, who will lead the new investigation, was the FBI's longest-serving director since J. Edgar Hoover, and oversaw some of the country's biggest cases, including the 9/11 attacks and the bombing at the Boston Marathon last year.

He stepped down last September and later joined a private law firm.