Rihanna's injuries at the hands of boyfriend Chris Brown has been described as "horrific" by law enforcement sources.

The Umbrella singer -  or Robyn Fenty as she is named in the crime report - says she was struck by Chris on Saturday night after she accused her man of flirting with another woman at Clive Davis' pre-Grammys party.

TMZ.com reports that photos of of the victim's injuries - a split lip, a bloody nose, contusions on both sides of the face and bite marks on her arm - taken by the police are "devastating proof of abuse."

No weapons were involved in the incident and and it has been confirmed that Rihanna refused treatment before she left the scene.

Both Rihanna and Chris pulled out of their scheduled Grammys performance on Sunday.

According to Life & Style, the couple were spotted rowing 24-hours before the alleged assault took place.

An onlooker says, “I saw Chris Brown and Rihanna fighting at the Verizon party at Boulevard 3 nightclub on Friday night.

“They were screaming ‘F*** you,’ ‘No, f*** you’ at each other, back and forth. They were right in each other's face.  

"It was scary.”

Rihanna with Chris were all smiles at a pre-Grammy's party on Saturday night, just hours before incident occurred