Mel Gibson and Oksana Grigorieva

Mel Gibson and Oksana Grigorieva (Getty Images)

LOS ANGELES -- A key witness in the Mel Gibson assault case involving ex-girlfriend Oksana Grigorieva has died.

RadarOnline is reporting that Gibson's babysitter, the one he labeled a "wetback" in audio recordings, died of cancer over the weekend.

The site reports that the unidentified woman was an eyewitness to the actor's alleged rage. According to Grigorieva, the babysitter witnessed Gibson storming around the house, slamming doors and screaming to someone over the phone, "I want to [expletive] destroy you."


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The woman never provided a statement direct to law enforcement investigators before she died.

She apparently left the actor's Malibu mansion before his alleged Jan. 6th rampage.

Grigorieva released audio recordings of the angry telephone conversations between her and Gibson.

The tapes are now in the hands of L.A. detectives investigating possible domestic violence.

Grigorieva is hoping to strip the Academy Award-winning actor of custody of their daughter, Lucia.

Her attorneys claim the audio tapes prove he is a danger to the child.

In one recording, Gibson is allegedly heard referring to the babysitter, saying, "I will fire (name omitted) if she's at your house. I will make it known and fire her. I'll report her to the (expletive) people that take (expletive) money from the wetbacks, ok?"

In another recording, Grigorieva accuses the actor of punching her in the face while she was holding their daughter. The Russian singer says two of her teeth were broken in the attack.

The person on the phone tells her she "deserved" to be hit. "What kind of a man is that?" she was heard saying. "Hitting a woman when she's holding a child in her hands? Breaking her teeth twice in the face! What kind of man is that?" "Oh, you're all angry now!" Gibson allegedly responds. "You know what, you ... (expletive) deserved it!"

The recordings may not be allowed into court during a criminal probe because they were made without Gibson's consent. In California, both parties must consent to have a telephone conversation recorded.