Troubled star Amanda Bynes has attacked singer Rihanna on Twitter, posting a series of racist and offensive remarks about the singer and her relationship with Chris Brown, according to the UK's Daily Mail.
The 27-year-old briefly posted several bizarre offensive tweets about Rihanna, 25, before deleting them.
The tirade began when Bynes wrote '@rihanna you look so ugly tryin (sic) to be white', followed by another tweet message blaming the singer for being assaulted by her ex-boyfriend.
'Chris Brown beat you because you're not pretty enough,' Amanda tweeted.
The actress then retweeted a post by Rihanna: 'Look who came to see me!! My lover Stella McCartney!!!' to which Amanda responded: ''No one wants to be your lover so you call everyone and their mother that I almost named my new dog Rihanna.'
Rihanna, responded with 'Ya see what happens when they cancel Intervention?,'
Bynes then shot back with an accusation Rihanna took drugs.
'Unlike ur fugly faced self I don't do drugs! U need the intervention dog! I met ur ugly face in person! U aren't pretty u know it! (sic)'