Prosecutors Friday began closing arguments in the trial of American student Amanda Knox for the gory murder of her British housemate in the Italian university town of Perugia two years ago. The killing of Meredith Kercher allegedly resulting from a drug-fueled sexual misadventure involving Knox, her Italian boyfriend and a drifter from the Ivory Coast sparked sensational headlines in Britain. Knox, wearing a long-sleeved tan knit top and blue jeans, flashed a smile as she entered the courtroom. Co-defendant Raffaele Sollecito, an engineering student, looked calm as he walked in wearing a white cotton jacket. Prominent prosecutor Giuliano Mignini, noting that the trial had sparked the interest of three continents, said 'detectives seeking fame, bloggers and mystery writers conducted a sort of parallel trial' in the media. 'But the trial is being carried out in this courtroom alone,' he said. Knox and Sollecito, who both proclaim their innocence, have been held since a few days after the murder, which occurred in the late evening of November 1, 2007. The third defendant in the case, Rudy Guede, was already convicted and sentenced to the maximum 30 years in prison for the murder in a 'fast-track' trial judged solely on the basis of the investigation. He is appealing the conviction. Central to the prosecutors' case is the supposed murder weapon, a knife found in Sollecito's apartment allegedly bearing Knox's DNA on the handle and the victim's DNA on the blade. Knox, now 22, Sollecito, 25, and Guede, 22, are accused of killing Kercher after she refused to join in a group sex session. Kercher was found semi-nude in a pool of blood with her throat cut in the house in Perugia, a medieval walled city in central Italy, that she shared with Knox. She was 21. In the prosecutors' scenario, Guede held Kercher down while Sollecito and Knox stabbed her. Kercher's family are seeking 30 million euros (40 million dollars) from the alleged killers. Knox's part-time employer at the time of the murder, bar owner and musician Patrick Lumumba of the Democratic Republic of Congo, is suing Knox for defamation. She initially implicated Lumumba in the murder, and Perugia police held him for two weeks before releasing him without charge. Mignini, who is expected to make his sentencing request Saturday, said Knox had 'knowingly accused an innocent person.' 'Amanda didn't move a finger while he was languishing in prison.' Two judges and six jurors will decide the fate of Knox and Sollecito, who face 30 years in prison if convicted. The jury is expected to begin deliberating on December 4, with a verdict expected the following day in the trial that began January 16. 