(CBS/AP) Last Updated 4:06 p.m. ET
PERUGIA, Italy - American student Amanda Knox, who was convicted by an Italian court for the 2007 murder of her roommate Meredith Kercher, was acquitted today by an appeals court.
Her murder conviction in the 2007 slaying of her roommate Meredith Kercher was thrown out by the jury, and she was ordered immediately released from prison after nearly four years of detention.
Knox collapsed in tears after the verdict was read out Monday.
Her former boyfriend Raffaele Sollecito was also found not guilty.
Knox and Sollecito had been convicted in 2009 of sexually assaulting and murdering Kercher, who was stabbed to death in her bedroom. She was found in a pool of blood and covered by a duvet the following day.
Knox was sentenced to 26 years in prison, Sollecito to 25. Also convicted in separate proceedings was Rudy Hermann Guede, an Ivorian man. They all denied wrongdoing.
The Kercher family looked on grimly as the verdict was read out by the judge after 11 hours of deliberations by the eight-member jury.
Outside the courthouse, some of the hundreds of observers shouted "Shame, shame!"
As the verdict was announced, about a dozen supporters from the group called Friends of Amanda, gathered at a downtown Seattle hotel to watch the proceedings on TV, burst into applause and cheered. They began chanting, "She's free!" and "We did it!"
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Earlier Monday, as hundreds of reporters and cameras filled the underground, frescoed courtroom, Knox tearfully told the Italian appeals court she did not kill her British roommate, pleading for the court to free her so she can return to the United States after four years behind bars. The court began deliberations moments later.
Knox frequently paused for breath and fought back tears as she spoke in Italian to the six members of the jury and two judges in a packed courtroom, but managed to maintain her composure during the 10-minute address.
"I've lost a friend in the worst, most brutal, most inexplicable way possible," she said of the 2007 murder of Meredith Kercher, a 21-year-old Briton who shared an apartment with Knox when they were both students in Perugia. "I'm paying with my life for things that I didn't do."
"She had her bedroom next to mine, she was killed in our own apartment. If I had been there that night, I would be dead," Knox said. "But I was not there."
"I did not kill. I did not rape. I did not steal. I wasn't there. I wasn't there at the crime," Knox said.
"48 Hours Mystery" correspondent Peter Van Sant reports that Knox appealed to the jury - members of which wept openly during her statement - to reverse the conviction and let her return home.
"I insist I'm innocent and that must be defended. I just want to go home, go back to my life," she told the court through tears.