ROME (USA TODAY) -- An Italian court Thursday reinstated the murder conviction of Seattle native Amanda Knox for the stabbing death of Knox's roommate, the latest twist in a dramatic, long-running case that is likely to be appealed again.

Knox, who was in Seattle while the court verdict was reached Thursday night in Florence, was sentenced to 28 1/2 years, while ex-boyfriend Raffaele Sollecito, also charged in the case, received 25 years. The pair had been charged with the grisly murder of Meredeth Kercher, a 21-year-old student found stabbed to death in the Perugia villa that she and Knox had rented in 2007.

In a statement, Knox said she was "frightened" and "saddened" by the verdict. She blamed overzealous prosecutors and a "prejudiced and narrow-minded investigation" for what she called a perversion of justice and wrongful conviction.

Knox and Sollecito will appeal the verdict. Their first two trials produced flip-flop verdicts of guilty,then innocent. The pair were acquitted on appeal in 2011 after spending four years in custody, when a court found that important evidence regarding blood and DNA had been handled improperly by investigators.

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But Italy's supreme court - called the Court of Cassation - dismissed that ruling based on what it said was key evidence that had been omitted during the appeal. A Florence appeals panel was subsequently designated by Italy's supreme court to address issues it raised about the acquittal.

Knox did not return to Italy for the latest trial, raising the possibility that Italian officials could request her extradition if the latest verdict is upheld. In recent days, Sollecito said he would be in court for the verdict, but in the end, his attorney, Giulia Bongiorno, said he stayed away because he felt too much stress.

Legal experts have said no extradition request would be made before a final judgment is handed down -- which means waiting months, perhaps longer, for the appeal process to play out. If a request is made, it is not clear what will happen next.

"Italy would usually refuse to extradite someone convicted of murder to the U.S. based on human rights grounds, because of the death penalty," said Argia Bignami, a Rome-based attorney and frequent commentator on criminal justice issues. "But that is not relevant for an extradition request to Italy from the U.S.

"But an extradition request is not automatic," she continued. "That's a further step that must be taken, and it's not at all clear how U.S. authorities would react to such a request or what would happen if they refused."

The verdict was a surprise to some experts: Philip K. Anthony, CEO of U.S.-based trial consultants DecisionQuest said the same trial might have played out differently if it had been held in another country.

"It's a little suprising that a jury would convict when there were questions about the DNA evidence," Anthony said. "The outcome would have likely been different in an American court with an American jury."

Knox told Italian state TV in an interview earlier this month that she would wait for the verdict at her mother's house "with my heart in my throat."

The high-profile case drew mixed reaction among Italians.

"I always thought they did it but I am still embarrassed this has gone on so long,'' said Giancarlo Milanese, a pre-law student. "So now there's an appeal. Four trials total is too much to go through."

Others were bothered that Knox refused to return for the latest trial.

"I have no opinion about guilt of innocence of these two, but it doesn't seem fair that one (Knox) stays at home, while Sollecito is brave enough to appear to hear the judgment," said 66-year-old Sabrina Vincente, a retired law firm office manager. "They either committed the crime together or they did not. It's not just to think the punishment would be given to only one half of the couple."

Contributing: Gary Strauss in McLean, Va., Associated Press