LOS ANGELES (AP) -- Los Angeles police say they're investigating an alleged domestic violence felony battery report involving Chris Brown.

The police department says in a release the 19-year-old R&B singer and a woman were in a vehicle in the Hancock Park neighborhood early Sunday when they began arguing. Police say Brown and the woman got out of the car and the argument escalated.

Police say the woman identified Brown as her attacker. Officers say Brown wasn't at the scene. A message left for Brown's representative seeking comment wasn't immediately returned.

Meanwhile, Entertainment Tonight has confirmed that Brown's girlfriend, pop singer Rihanna was involved in a car accident this morning and will not be performing at tonight's 51st Annual Grammy Awards.

A Grammy representative told ET that the singer's face is slightly bruised from the accident and no announcement has been made as to who will be taking her place on stage.