Has Chris Brown attacked Rihanna before?

Was eye patch cover-up for past attack?

Police are investigating allegations that pop star Rihanna may have been injured by her boyfriend Chris Brown in the past.

According to The Sun, LA police are looking into an alleged history of violent rows between the pair.

Rihanna was last year seen sporting an eye patch at the American Music Awards 2008, which, she said, was because of a scratched cornea.

But a source told the newspaper: ‘We’re investigating if her eye injury could have been caused by Brown.

‘There could be an innocent explanation - but police believe Rihanna has previously refused to make a complaint against Brown.

‘She is now being asked about her past injuries and is beginning to open up about incidents in their relationship.’

Another police source added: ‘We’re talking to her friends and management, who say she’s appeared with mysterious marks or injuries before, but always refused to explain what happened.'

Reports also claim Rihanna was spotted with a bruise on her neck in December – but the singer did not explain how she got it.

The Umbrella star suffered a bloody nose, a swollen lip and facial bruising in an alleged row with Brown just hours before last Sunday’s Grammy Awards.

Brown has now jetted to Las Vegas, after being arrested and charged with making criminal threats.

He’s also found time to update his Facebook status to ‘single’ adding: 'You'll begin to see her true colours. Believe it.’

Friends are said to be outraged by the alleged incident, with Rihanna’s former tour mate, Kanye West, telling E! News: 'I don't want to speak more into the specifics with that situation, but all I'll say is it's just so devastating.

'I feel like, just as a person, I don’t care how famous she is or even if she just worked at McDonald's, that should never happen. It should never come to that place.'

Meanwhile, Leona Lewis has denied claims it was a conversation with Chris Brown that prompted his alleged row with Rihanna.

The X Factor star was seen chatting to Chris at a pre-Grammys do.

A source told the Daily Mirror: ‘Rihanna saw Chris flirting. He and Leona were laughing and Rihanna saw his hand on the small of her back.

‘It was totally innocent but it set Rihanna off.’

But Lewis's spokeswoman said: 'This has nothing to do with Leona.'

SEE AL THE GLAMOROUS GRAMMY PICS HERE