PERUGIA, Italy (AP) " Amanda Knox headed home to the United States a free woman Tuesday, the morning after an Italian appeals court dramatically overturned the American student's conviction of sexually assaulting and brutally slaying her British roommate.
The Italy-US Foundation, which has championed Knox's cause, said she departed shortly after noon (1000 GMT) from Rome's Leonardo da Vinci airport on the way to London, from where she will catch a connecting flight to the United States.
The 24-year-old Knox, who is returning to Seattle, arrived at the airport in a Mercedes with darkened windows and waited for boarding inside a private waiting area, out of public view.
Back in Perugia, the family of slain British student Meredith Kercher remained stunned by the verdict and searching 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 is still trying to understand how a decision that "was so certain two years ago has been so dramatically overturned."
Lyle Kercher said the family has been left to wonder who is guilty in the 21-year-old Kercher's death after the release of Knox and her one time boyfriend Raffaele Sollecito on appeal. 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.
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 in 2009 of sexually assaulting and murdering Kercher, a 21-year-old British student 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.
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, who was with Knox 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 on Monday night 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 that his son remained stunned by the events.
"He is trying to recover himself," Sollecito's father told reporters outside, the news agency ANSA reported. "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.
"We still trust the Italian justice system and hope that the truth will eventually emerge," the Kerchers said in a statement.
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.
The verdict reverberated through the streets of this medieval hilltop town, where both Knox and Kercher had arrived for overseas studies programs four years ago.
Hundreds of mostly university-age youths gathered in the piazza outside the courtroom jeered as news of the acquittals spread. "Shame, shame," they yelled, adding that a black man had been made to shoulder all of the guilt for the murder.
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.
Prosecutors said they would appeal to the nation's highest criminal court, after reading the court's reasoning due out within 90 days.
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."
Patricia Thomas contributed to this report.Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
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