A police statement said the 19-year-old R&B singer argued with an unidentified woman Saturday night, and that the fight escalated when they exited a car in the ritzy Hancock Park neighborhood. The woman told authorities that her attacker was Brown, who was not at the scene.
A representative for Brown had no comment when approached at the Staples Center, where the awards ceremony was being held. Brown had not been spotted there as of late Sunday afternoon.
Brown has long been dating pop superstar Rihanna, who was slated to perform. But she dropped out, the Recording Academy said in a statement less than an hour before the show.
In the midst of the Brown's bad news, there was some pre-ceremony Grammy good news.
Lil' Wayne won three Grammys, Robert Plant and Alison Krauss won a pair while Carrie Underwood, Coldplay and Radiohead snagged one apiece as the Recording Academy doled out the bulk of their 110 trophies during the pre-telecast ceremony.
Lil' Wayne was the nominations leader with eight, and won best rap solo performance for "A Milli," rap song for "Lollipop" and rap/sung collaboration for "Swagga Like Us," an all-star song featuring Jay-Z, T.I. and Kanye West.
But the prolific rapper won't be going home with eight trophies; he was competing against himself in two categories that he won and lost another. He still has a chance to win the evening's top prize, album of the year, for his best-selling disc "Tha Carter III."
Plant and Krauss, also nominated for album of the year for their collaboration "Raising Sand," were also early winners, taking home an award for country collaborations with vocals and contemporary folk/Americana album.
Unlike most top names nominated in the pre-telecast, Underwood showed up to accept her Grammy for female country performance.
"There's no way this could ever on this planet get old," said Underwood as she accepted her trophy.
Coldplay, up for seven Grammys, won best pop performance by a duo or group with vocals for "Viva La Vida," while Radiohead won best alternative music album for "In Rainbows."
It is a category they are familiar with. Though they have sold millions by making some of the most daring and genre-defying music of the last two decades. But even with their industry-changing "In Rainbows," they've always seemed to be stuck in the alternative world.
Though they've been twice nominated for an album-of-the-year Grammy, their two Recording Academy trophies are in the alternative category. Could a best-album win on Sunday elevate the critically revered group to a new - and decidedly more mainstream - level?
Jonny Greenwood, the group's multi-instrumentalist, thinks those are good questions to ask. And he isn't quite sure the answers matter.
"I don't know, I'm curious," he wondered before a rehearsal for the Sunday telecast, during which Radiohead is set to perform. "Are we the kind of band that it would change anything, really? It's sort of hard to imagine that it would."