"Chris knocked her around," a source close to the couple tells PEOPLE. "Black eye, blood, bruises. She had to be treated by a doctor."
A police source confirms to PEOPLE that the singer suffered a black eye as well as "a swollen split lip and two red and purple contusions on either side of her forehead."
The source, who described police photos of Rihanna, added, "She looked distraught and in a lot of pain. Her eyes were closed because she was looking down."
The Barbados-bred beauty, 20 – who is currently in "a safe place," says a friend – is cooperating with detectives, according to the Los Angeles Times. Los Angeles Police Chief William Bratton has said he expects the case will be handed over to the district attorney's office on Tuesday or Wednesday. At that time, the prosecutors could charge Brown, 19, with more crimes.
The case could be affected by how much Rihanna is willing to forgive her boyfriend. "Prosecutors back off somewhat when they see a couple trying to work out their own issues," says Steve Sitkoff, an L.A. defense attorney. But, says the friend, "I would be so sad if she went back to him."
In the meantime, both stars have canceled upcoming appearances: The NBA has issued a statement that Brown will no longer participate in their All-Star Game events in Phoenix this weekend, while Rihanna backed out of a Friday night concert in Malaysia.
Friends Call Brown a Good KidNews of the alleged assault stunned fans and friends alike. Brown, known for his charm and Michael Jackson-style moves, has always been seen as a good kid. "I've never known Chris to be combative," says his high school gym teacher from Tappahannock, Va., Lyn Amos. "He's always low-key, easygoing." Adds Jean Segar, a restaurant owner who has known Brown since he was a child: "He's such a mild-mannered person. It's hard for me to believe [the charge]."
What makes the allegations even more shocking is that Brown has claimed his mother was physically abused by his former stepfather. "He made me terrified all the time," Brown told Giant, adding, "I hate him to this day."
The abuse allegations could have a long-lasting impact on Brown's career. On Monday, Wrigley temporarily suspended his Doublemint commercials, and as an industry source points out, "A lot of his fans are women."
Reporting by TIFFANY MCGEE, WENDY GROSSMAN, JESSICA HERNDON and KEN LEE
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