LOS ANGELES, California (CNN) -- The woman allegedly assaulted by singer Chris Brown in Hollywood early Sunday was his girlfriend, singer Rihanna, according to sources close to the couple. Chris Brown attends a party saluting music producer Clive Davis in Beverly Hills, California, on Saturday. While Los Angeles Police have a policy against identifying alleged domestic violence victims, two people who know both Brown and Rihanna confirmed she was the woman police said had "suffered visible injuries and identified Brown as her attacker." Brown, 19, turned himself in to police Sunday night after police said they were looking for him. He was arrested on suspicion of making criminal threats.
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Brown has been arrested in connection with a domestic violence incident
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Police: Brown turned himself in after woman accused him of attacking her
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Brown a no-show at Grammy Awards, where he was to perform Sunday
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Police haven't named woman; Brown's girlfriend, Rihanna, cancels performance
"After stopping his car, @placeholder and the woman got out and the argument escalated," police said.