The parents of an American student accused in a sensational Italian sex slaying said in an interview broadcast Friday that their daughter could never have done such a crime.

Amanda Knox tells her parents, "Why am I here when I didn't do anything?" her father, William Knox, said in the interview on ABC's "Good Morning America." It was the parents' first extensive interview since the November slaying of Meredith Kercher.

Kercher, a 21-year-old British student, was found dead in the apartment she shared with Knox in the central Italian town of Perugia where both were studying. She had been sexually assaulted and died of a knife wound to the neck.

Amanda Knox, a University of Washington student from Seattle, was taken into custody along with two other people in connection with the death.

"She says she's tired a lot," her mother, Edda Mellas, told ABC. "Jail's not easy."

The parents said the coverage of the case, which has portrayed their 20-year-old daughter as a sexually adventurous woman, has been unfair. "One hundred eighty degrees opposite of anything we have ever known her to be," her father said. Asked if she could have committed a crime, he said: "Never. ... It's not her."

Further material from the interview was to be broadcast later Friday on the network's "20-20" program.

Knox and her then-boyfriend, Raffaele Sollecito, 23, were jailed Nov. 6. A judge has ruled that both can be held for as long as a year while the investigation continues. The third person in custody is Rudy Hermann Guede, a student from Leeds University in England and a native of Ivory Coast.