Ex-FBI Head Investigating NFL's Handling of Ray Rice Matter

Former FBI director Robert S. Mueller III will conduct an independent investigation into the NFL's pursuit and handling of evidence in the Ray Rice situation, league Commissioner Roger Goodell announced.

The league has come under increasing scrutiny following the February assault between Rice and his then-fianc Janay Palmer in a hotel elevator. A police report at the time stated that Rice committed assault "by striking her with his hand, rendering her unconscious."

Within days of the incident, surveillance video from outside the elevator emerged, showing Palmer - now married to Rice - unconscious. The NFL's efforts to acquire additional surveillance video from inside the elevator, showing the actual attack, remain unclear.

Rice, 27, was initially suspended for two games. But after the second video was released by TMZ.com Monday, showing Rice punching the woman, the Baltimore Ravens terminated Rice's contract and the NFL suspended him indefinitely.

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The NFL's announcement follows an Associated Press report that a law enforcement source sent video of the attack to the NFL three months ago and played a voicemail for the AP of the source's phone call to the NFL in which a woman acknowledged receiving the video and saying, "You're right. It's terrible."

The NFL issued a statement in reaction to the AP story.

"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. We will look into it," the statement said.

Both the team and league have said they asked for the video, but police and prosecutors did not turn it over because it was part of a grand jury hearing.

But two sources briefed on the incident and behind-the-scenes discussions regarding the tape told ABC News that the Ravens knew that the tape existed and knew what was on the tape almost immediately after the incident.

Mueller's investigation will be overseen by NFL owners John Mara of the New York Giants and Art Rooney of the Pittsburgh Steelers - and the final report will be made public, the league announced.

Mueller, 70, served as director of the FBI from 2001 until 2013, and is currently a partner in the law firm of WilmerHale. He is based in Washington, D.C.

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