An Italian criminal court ordered Amanda Knox to stand trial again for the murder of her roommate on Tuesday.

The Court of Cassation, Italy's final court of appeal overturned the acquittals of Knox and ex-boyfriend Rafaelle Sollecito over the 2007 murder of Meredith Kercher. When the judge read the decision, the courtroom was shocked and greeted by a silence, The New York Times reported.

"It was painful to receive the news that the Italian Supreme Court decided to send my case back for revision when the prosecution's theory of my involvement in Meredith's murder has been repeatedly revealed to be completely unfounded and unfair," Knox said.

Knox who is now 25 and Sollecito were initially convicted of murder, but was acquitted on appeal 18 months ago. The prosecutors challenged the appeal and the case will be reheard at a new appeal court in Florence later this year or in 2014. 

Meredith, a 21-year-old British exchange student at the University of Perugia was murdered in her bedroom on Nov. 1, 2007. She was found half-naked under a blanket with her throat split open.

Prosecutors argued that Knox and Sollecito killed Meredith after a drug-fueled sexual assault. The case attracted worldwide attention.

Knox and Sollecito were arrested and convicted of murder in December 2009 in a lower court in Perugia. 

The two were convicted and found guilty of murdering Meredith. Knox was sentenced to 26 years in jail, while Sollecito received 25, but they were acquitted after only serving four years.

"The prosecution responsible for the many discrepancies in their work must be made to answer for them, for Raffaele's sake, my sake, and most especially for the sake of Meredith's family. Our hearts go out to them," Knox said.

Meredith's sister Stephanie Kercher, 29, told Britain's ITV News that the family accepted the court's decision to retry Knox and Sollecito so that they can gain closure and find the answers leading up to the killing of Meredith.

"We are never going to be happy about any outcome because we have still lost Meredith, but we obviously support the decision and hope to get answers from it," Stephanie said.

Knox's lawyer, Theodore Simon, told Today that Knox and her family will fight against the allegations and was confident that her acquittal would be upheld. 

Knox's Waiting to Be Heard book about the case is scheduled to be released in April.

Tags: amanda knox