Why Did Amanda Bynes Blast Rihanna on Twitter?

Amanda Bynes has had a rough week, but the troubled star didn't do herself any favors when she lashed out at Rihanna via Twiter on Sunday.

"Chris Brown beat you because you're not pretty enough," Bynes wrote according to  E! News, completely unprovoked. "No one wants to be your lover so you call everyone and their mother that I almost named my new dog Rihanna," she added.

Amanda Bynes accuses arrested police officer of sexual harassment

Shortly after, Bynes deleted her tweets but that didn't stop Rihanna from firing back: "Ya see what happens when they cancel intervention?"

Only days after being arrested for throwing a bong out her window, Bynes continued to insist on her sobriety. "unlike ur ugly 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!" she wrote.

The feud seems to have since ended, but we wouldn't be surprised if Bynes found another new target soon.