Amanda Knox has vowed to fight a new verdict that was handed down to her by an Italian court Thursday, finding her guilty for the second time of murdering an ex-roommate.

The 26-year-old appeared on Good Morning America Friday morning, where she vowed to fight the new verdict, which comes after she was previously acquitted of murder charges.

"They found me innocent before, how can they find me guilty beyond a reasonable doubt?" she said.

The new verdict is the latest twist in a dramatic story which began back in 2007, when Knox and her ex-boyfriend, Raffaele Sollectio, 29, were charged in the murder of Knox's Perguia flat mate, British exchange student Meredith Kercher.

Knox was originally convicted of the crime and spent four years in an Italian prison before an appeals court threw out her conviction in 2011. However, Italy's supreme court ordered the case to be retried, resulting in a second guilty verdict now.

Knox has now been sentenced to a 28-year prison sentence, while Sollecito is required to serve 25 years.

"I couldn't believe what I was hearing," she said about watching the trial on an Italian television station from her Seattle home. "This really has hit me like a train. I did not expect this to happen. I really expected so much more from the Italian justice system."

However, Knox maintains her innocence and said she will fight the verdict.

"I'm not prepared. I will never willingly go back," she said. "I'm going to fight this until the very end. It's not right and it's not fair and I'm going to do everything I can. But I need a lot of help. I can't do this on my own."

The decision on whether Knox can be extradited back to Italy to serve her sentence is up to the U.S. Supreme Court.

For now, Know said she is worried about her ex-boyfriend, who is still in Italy and has had his passport revoked due to the new verdict.

Knox also revealed that she has thought of Kercher's family, and even wrote them a letter expressing her sadness for them.

"I just want them to know that I really understand that this is incredibly difficult. When the case has been messed up so much, a verdict is no longer consolation for them," she said.

"The thing that people want when they've been victims is just simple acknowledgement -and they deserve respect and that's been lost. I wish them the best."

Watch parts of Knox's appearance on GMA  below.



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