Chris Brown Punched Rihanna, Threatened to Kill Her

A detective's notes from the scene of the alleged Rihanna assault reportedly reveal disturbing details about what happened between the singer and her boyfriend Chris Brown in the early hours of Feb. 8.

According to FOX 11 in Los Angeles, which claims to have obtained the notes from a search warrant in the case, Rihanna, 21, read a lengthy text message from a woman on Brown's phone, which led to an argument. Brown – who has a standing court date Thursday – allegedly tried to force his girlfriend out of the Lamborghini, and hit her head against the passenger window.

Brown, 19, then punched the singer while still driving, according to the detective's notes, and blood filled Rihanna's mouth. He allegedly told her, "I'm going to beat the ---- out of you when we get home." Rihanna called her assistant and left a message saying, "I am on my way home. Make sure the cops are there when I get there." The police notes say that prompted Brown to reply: "You just did the stupidest thing ever. I'm going to kill you."

The report also says that Brown bit Rihanna and put her in a headlock, and that she almost lost consciousness.

Almost three weeks after the incident, the couple reunited in Miami Beach last week.

Contacted by PEOPLE, LAPD spokeswoman April Harding said, "We cannot confirm" the detective notes.

Via people.com