Updated

LAPD detective notes from a search warrant in the Chris Brown case, obtained exclusively by FOX 11 in Los Angeles, detail a horrific assault in the early morning hours of Feb. 8, the day Brown and girlfriend Rihanna were scheduled to perform for the Grammy Awards.

According to FOX 11, the notes reveal in shocking detail Brown shoving Rihanna's head against the window of his rented Lamborghini, repeatedly punching and biting her, and yelling, "I'm going to beat the **** out of you when we get home. You wait and see."

Brown is expected to appear Thursday in a Los Angeles courtroom to face possible charges in the case.

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The alleged blow-by-blow happened as follows, according to FOX 11.

After Rihanna read a text message on Brown's phone from a woman, he tried to force Rihanna out of the car, but couldn't because she was wearing her seatbelt.

VIDEO: Click for FOX 11's exclusive report.

Brown then allegedly slammed Rihanna's head against her window, and when Rihanna turned to face him, he punched her.

The notes said blood spattered on Rihanna's clothing and the interior of the Lamborghini.

PHOTOS: Click for Radar Online's photos of a blood-spattered Lamborghini.

Rihanna also called her assistant, according to FOX 11, leaving a message saying, "I am on my way home. Make sure the cops are there when I get there."

Brown then reportedly replied, "You just did the stupidest thing ever. I'm going to kill you," and proceeded to punch and bite Rihanna. He allegedly put her in a headlock so long that she almost lost consciousness.

Brown and Rihanna have since reportedly reconciled.