Brown under investigation after altercation last night

Rihanna has pulled out of her performance at tonight’s Grammy Awards, with no explanation given as yet.

The singer’s boyfriend Chris Brown is under investigation due to an alleged altercation shortly after leaving Clive Davis’s pre-Grammy party last night, during which an unidentified female was reportedly injured.

The LAPD stress there have been no arrests made, says Ken Baker of Us Weekly magazine, who revealed the news just moments ago on the Grammy red carpet.

Brown has also apparently pulled out of his scheduled appearance at the awards, and is rumoured to be replaced by Al Green or Justin Timberlake. Brown is nominated in two categories this evening.

–By our New York staff.

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