Rihanna and her partner Chris Brown pulled out of the Grammy Awards last night after Brown was arrested on assault charges.

The alleged incident happened shortly after the pre-Grammys gala at the Beverly Hilton in Los Angeles in the early hours of Sunday morning (February 8).

When police arrived at the scene at approximately 12.30am Brown had already left, but an unnamed woman with 'visible injuries' identified him as the attacker.

19-year-old Brown turned himself into police at 19.00 local time on Sunday and was released on $50,000 bail about an hour after the ceremony had ended.

In a statement, police described the incident outside the Hilton: "After stopping his car, Brown and the woman got out and the argument escalated. The woman suffered visible injuries and identified Brown as her attacker."

Rihanna was due to sing 'Love Your Life / Disturbia' at the Staples Center ceremony while Brown was to perform 'Forever'.

Shortly before the ceremony started, organisers released a statement saying: "We have just been informed that Rihanna will not be attending tonight's 51st Annual Grammy Awards. We're sorry she is unable to join us."

(by Scott Colothan)