Amanda Bynes calls Rihanna 'ugly'

Amanda Bynes took a jab on R&B star Rihanna by posting offensive messages on Twitter, saying the 'Diamonds' singer gets beaten by her ex-boyfriend, Chris Brown, because she is "not pretty enough".
"You look so ugly trying to be white," Bynes tweeted out.
Referring to Brown's infamous assault on the 'Diamonds' singer back in 2009, Bynes said, "Chris Brown beat you because you're not pretty enough. No one wants to be your lover so you call everyone and their mother that I almost named my new dog Rihanna," she continued.
Responding to Bynes' messages, Rihanna tweeted, "Ya see what happens when they cancel Intervention." Bynes later fired back, saying, "Unlike your fugly faced self I don't do drugs! You need the intervention dog! I met your ugly face in person! You aren't pretty you know it! (sic)"

Bynes has now deleted the tweets. It's not the first time the troubled actress ranted about other celebs on Twitter, reported Aceshowbiz.
Earlier this month, Bynes argued with model Jenny McCarthy after the 40-year-old star said that cops were on Bynes' house to help the troubled star.