PERUGIA, Italy -- Amanda Knox headed home to the United States a free woman Tuesday, after an Italian appeals court dramatically overturned the American student's conviction of sexually assaulting and brutally slaying her British roommate.
The family of 21-year-old victim Meredith Kercher appeared overwhelmed at the ruling, saying they were shocked and bewildered by the stunning reversal of the 2009 decision. The prosecutor said he would appeal the decision releasing Knox and her co-defendant and one-time boyfriend, Italian Raffaele Sollecito.
The case has been a cause celebre in the U.S., and a staple of British tabloids, which took to calling her "Foxy Knoxy." Throughout the four-year case, Knox was portrayed either as a femme fatale with an angel face or a naive young woman caught up in a judicial nightmare.
The verdict was controversial. Hundreds of mostly university-age young people gathered in the piazza outside the courtroom in Perugia, jeered and yelling, while Knox's supporters in her home town of Seattle hugged and shouted in joy.
British tabloids played up the drama of Knox's release -- and the Kerchers' pain. The "Daily Mail" headline read "Weeping Foxy is Freed to Make a Fortune," referring the reports that Knox could earn a paycheck in the U.S. for an exclusive interview.
Back in Perugia, Kercher's family searched for answers.
"It was a bit of a shock," said Stephanie Kercher, the victim's older sister. "It's very upsetting ... We still have no answers."
Lyle Kercher, a brother, said the family has been left to wonder who is guilty. A third man has been convicted in the brutal slaying, however his trial concluded he did not act alone.
"If the two released yesterday were not the guilty parties, we are obviously left to wonder who is the other guilty person or people. We are left back at square one," Lyle Kercher said.
The 24-year-old Knox arrived at the Rome airport in a Mercedes with darkened windows and waited for boarding inside a private waiting area Tuesday, out of public view and away from the media scrum. She headed to London, where she will catch a connecting flight to the United States.
Prosecutor Giuliano Mignini expressed disbelief in the verdict, and vowed an appeal to Italy's highest criminal court.
"Let's wait and we will see who was right. The first court or the appeal court," Mignini told The Associated Press on Tuesday.
"This trial was done under unacceptable media pressure. The decision was almost already announced; this is not normal," he said.
If the highest court overturns the acquittal, prosecutors would be free to request Knox's extradition to Italy to finish whatever remained of a sentence. It is up to the government to decide whether they make such a request.
Knox and Sollecito were convicted of sexually assaulting and murdering Kercher, who shared an apartment with Knox in Perugia. Knox was convicted to 26 years, Sollecito to 25. Both had been in prison since Nov. 6, 2007, four days after Kercher's body had been found at the apartment.
But, the prosecution's case was blown apart by a court-ordered DNA review that discredited crucial genetic evidence.
The jury upheld Knox's conviction on a charge of slander for accusing bar owner Diya "Patrick" Lumumba of carrying out the killing. The judge set the sentence at three years, less than the time Knox had spent in prison.
Knox dissolved into tears as the verdict was read in a packed courtroom after 11 hours of deliberations, and she needed to be propped up by her lawyers on either side. Two hours later, she was in a dark limousine that took her out of the Capanne prison just outside Perugia, where she had spent the past four years, and headed to Rome.
"During the trip from Perugia to Rome, Amanda was serene," said Corrado Maria Daclon, the secretary general of the Italy-US Foundation, a group backing Knox, who was with her in the car. "She confirmed to me that in the future she intends to come back to our country."
On Tuesday, Knox thanked those Italians "who shared my suffering and helped me survive with hope," in a letter to the foundation.
"Those who wrote, those who defended me, those who were close, those who prayed for me," Knox wrote. "I love you, Amanda."
Sollecito, meanwhile, arrived back home near the southern Italian city of Bari before dawn on Tuesday. He was quoted by Italian news agencies as saying he was looking forward to seeing the sea, but he declined to make any appearances after reaching home.
Sollecito's father Francesco said his son remained stunned by the events.
"He is trying to recover himself," Sollecito's father told reporters. "He is going around touching things as if he is a child who needs to take back the things of his life, to acquire forgotten elements."
While waves of relief swept through the defendants' benches in the courtroom, members of the Kercher family, who flew in for the verdict, appeared dazed and perplexed. Her sister Stephanie shed a tear, while her mother Arline looked straight ahead.
The Kerchers had pressed for the court to uphold the guilty verdicts, and resisted theories that a third man convicted in the case, Rudy Hermann Guede, had acted alone. Guede, convicted in a separate trial, is serving a 16-year sentence.
Just before deliberations began Monday, Knox tearfully told the court she did not kill her roommate.
"I've lost a friend in the worst, most brutal, most inexplicable way possible," she said. "I'm paying with my life for things that I didn't do."
Knox and Kercher were in the medieval Umbrian town of Perugia to study abroad.