Amanda Bynes slams the media again via Twitter after being arrested at her apartment on Thursday.  Amanda also blasts Rihanna calling her ugly in tweets that were later deleted. The twitter war between Amanda Bynes and Rihanna comes out of nowhere. What's the beef about?

The dual Rihanna bashing and Twitter rants come days after police arrested Amanda for suspicion of drug paraphernalia and a bong previously thrown out her window.

Amanda Bynes tweets, "I only smoke tobacco I don't drink or do drugs. I've never had a bong in my life!" she told her some 1.1 million Twitter followers hours after she appeared in court, adding: "I need to get another nose job after seeing my mugshot! :D."

She also reiterated that she threw a vase out of her apartment window Thursday evening, and not a bong.

After defending her actions on Twitter, the child star let her followers know how much she despises singer Rihanna.

"@rihanna Chris Brown beat you because you're not pretty enough," she posted in a deleted message on her Twitter account. E! Online has the screenshots of the original posts.

The actress went on to criticize Rihanna. "@rihanna no one wants to be your lover so you call everyone and their mother that I almost named my new dog Rihanna."

While the Tweets have since been deleted, Rihanna be insulted by Bynes' rant. The 25-year-old singer posted a cryptic message on her account moments after Byne's rude comments, which was not addressed to anyone in specific.

While the singer didn't mention Bynes' Twitter handle in her Tweet, the actress took the message personally, posting: "Ya see what happens when they cancel Intervention?"

Amanda didn't like those comments firing back, "@rihanna 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!"

So why such animosity between the two stars?

The Barbadian-born Rihanna did have a fling with rapper Drake, for whom Bynes has confessed a love - once saying she wanted him to "murder" her private parts.

Amanda Bynes is rapidly falling apart.  If you didn't know about her arrest here's what happened:

On Thursday night, actress Amanda Bynes was arrested by New York police after allegedly throwing drug paraphernalia out of her window. The police were called to her Midtown Manhattan West 47th Street apartment.

Police were called to her home after the building manager reported that the 27-year-old actress was smoking an "illegal substance" in the lobby, Christopher Pisano, a New York police spokesman, said.

By the time police arrived, Bynes was already back in her apartment, but let the officers in when they knocked on her door, according to Pisano.

Once officers were inside the apartment they noticed a bong and other marijuana paraphernalia sitting on the actress's coffee table, which she immediately started to throw out the window.

The star, wearing a blonde wig, was seen walking into NYPD's Central Booking from the back of a police van.

She's been charged with tampering with physical evidence, reckless endangerment and criminal possession of marijuana. While the tampering charge is a felony, the other two are misdemeanors.

Police said Bynes was charged with endangerment because the paraphernalia could have hit someone below.

This isn't Bynes' first run in with the law. She has a DUI case pending in Southern California as well as a pair of separate hit-and-run incidents against her, though they were dismissed late last year.

Earlier this month, she was sentenced to three years probation for driving on a suspended license.