Italy’s highest appeals court has criticised "glaring errors in the investigation into the 2007 murder of British student Meredith Kercher.

The court acquitted Amanda Knox and her ex-boyfriend Raffaele Sollecito of the murder in March.

It said there was an “absolute lack of biological traces” of either defendant in the room where Ms Kercher was killed and on her body.

Kercher, 21, was stabbed to death in a Perugia flat she shared with Ms Knox.

The Court of Cassation, which exonerated the pair, published its reasoning on Monday, as it is required to do under Italian law.

It issued a damning assessment of the quality of the prosecution case, saying its high profile nature had an effect on investigators.

“The international spotlight on the case in fact resulted in the investigation undergoing a sudden acceleration,’’ the court said.

Several mistakes in the investigation were outlined by the court in its reasoning, including the fact that investigators burned Knox’s an Kercher’s computers, which could have yielded new information.

The court also wrote that the Florence appeals court which convicted the pair last year ignored expert testimony that "clearly demonstrated possible contamination of evidence and misinterpreted findings about the knife allegedly used to slit Kercher’s throat, in what prosecutors had described as a sexual assault, AP reports.

The kitchen knife, found in Sollecito’s house and the supposed crime weapon, was kept in an ordinary cardboard box, the judges noted, adding that no traces of blood were found on it.

The judges said that one of Ms Kercher’s bra clasps, which prosecutors argued carried a trace of Mr Sollecito’s DNA, was left on the floor of the murder scene for 46 days, and then “was passed from hand to hand of the workers, who, furthermore, were wearing dirty latex gloves”.

Another man, Rudy Hermann Guede, born in Ivory Coast, was convicted of murder in a separate trial and is serving a 16-year sentence.

The court’s ruling against Guede stated that he did not act alone, but the acquittals of Knox and Sollecito mean that no-one now stands convicted of acting with Guede to kill Kercher.