An update on Amanda Knox's retrial revealed that BBC has released the audio interview of "Foxy Knoxy" for its new documentary six years after it was made. The recording was taken while she was being interrogated in prison over the death of her roommate Meredith Kercher in 2007.

The audio clip is part of the documentary titled "Is Amanda Knox Guilty?" which is aired by BBC Three.

As reported by UK's Mirror, Amanda Knox was heard on the audio claiming that the Italian authorities "were telling me that I was guilty" in the effort to make her confess.

Meredith Kercher was stabbed 40 times and had her throat slashed in a gruesome murder that gripped Italy. Rudy Guede was later convicted in October 2008 and sentenced to 30 years.

Amanda Knox and her ex-boyfriend Raffaele Sollecito were later haled to court for the murder and initially exonerated of the crime. However, they were indicted by an appellate judge who sentenced the American student to 28 and ½ years in prison.

The lawyer for the prosecution, Manueala Comodi, told BBC that due to the manner which Meredith Kercher was killed, it's impossible for Rudy Guede to do it alone because "not even Superman could do it."

"One person couldn't - all at the same time - hold Meredith still and hold back her hands, because there are very few defensive wounds, inflict those wounds with a smaller knife and then give her the fatal blow with the larger knife. It is impossible," she said.

Forensic biologist Sarah Gino, however, said the evidence was inconclusive because the case only used test reults for blood. "Was the test done for saliva? No. So we can't know if inside that mixed trace there was blood because it had been demonstrated or just saliva," she said.

She explained that the time element could not be definitely proven. It could be that Amanda Knox cut herself at one point and her blood got mixed with Meredith Kercher's blood.