By Breaking Celebrity News Staff

The murder conviction of Amanda Knox was overturned by an Italian court on Monday and she is free to leave prison and return to the U.S.

The verdict in the appeals case was announced on Monday at 9.50 p.m. local time.

Knox cried hysterically with joy as she heard the ruling in the medieval Perugia, Italy courtroom, as a crowd of up to a thousand people gathered in the piazza outside, some of whom were booing.

Knox was found guilty of defamation for implicating her former boss, Patrick Lumumba, in the crime. She was sentenced for three years for those charges, but has already served almost four years, so she is a free woman.

As Breaking Celebrity News previously reported, the American exchange student, 24, had appealed her conviction for the murder of her British roommate Meredith Kercher.

Earlier Monday, Knox tearfully addressed the appeals court and said: "I did not kill. I did not rape. I did not steal," she added. "I was not there."