Chris Brown and singer Frank Ocean are alleged to have got involved in a fight on Sunday night.
Police were called after the singers were involved in an altercation over a parking space.
The incident is reported to have happened when the controversial R & B star left the Westlake Recording studio in the Los Angeles area where he had been listening to one of the artists he represents.
According to TMZ, Brown went to leave the studio but 'was blocked by Frank Ocean and his crew.'
Sources told the website that Ocean said: 'This is my studio, this is my parking spot,' adding that Brown 'went to shake Ocean's hand when he was 'attacked by one of Frank's people.'
An insider connected with Brown claimed one of the singer's friends 'jumped in front and hit Frank's head.'
Ocean then 'came at Chris. Chris pushed him away and they started brawling,' sources added.
However, Ocean has a different version of the story: 'Got jumped by Chris and a couple guys lol,' he wrote on Twitter. 'I only wish everest was there.
He then added: 'Cut my hand now I can't play with two hands at the grammys.'
This is not the first time the two singers have been involved in conflict.
Last July, Brown was forced to deny aiming a homophobic slur towards Ocean when asked his opinion on the star.
He denied making the comments on his Twitter page, posting: 'My Opinion on the whole Frank Ocean subject is ......... Love who u wanna love. It's ur decision. People stop searching for BS.'
Ocean came out as gay in a post on his blog last year.