Traces of at least two unknown people were discovered at the London apartment of a British spy whose naked body was found locked inside a duffel bag, a forensic expert told a hearing Monday.
Ros Hammond said that DNA from two unidentified people had been found inside the home and that ongoing tests could provide a breakthrough in the case, which has so far baffled investigators.
Gareth Williams, 31, worked for Britain's secret eavesdropping service GCHQ but was attached to the MI6 overseas spy agency when his remains were found in August 2010 at his London apartment inside the bag, which had been placed in a bathtub.
"There's certainly evidence of at least two people other than Mr. Williams on the samples tested," Hammond told an inquest hearing at Westminster Coroner's Court.
Police said they are not certain exactly how Williams died and have so far made no arrests, although a senior detective has told the inquest she believes that at least one other person must have been involved.
Officers have suggested that Williams' death may have had links to his private life and his apparent interest in sadomasochism, possibly during a sexual encounter gone awry. His relatives, however, insist that his demise must be related to his highly secret work.
MI6 colleagues failed to report Williams as missing for a week, meaning that police and pathologists lost vital chances to gather evidence.
Pathologist Benjamin Swift told the inquest that radiators had been turned on inside Williams' apartment -- even though it was summer -- accelerating the decomposition of his body.
Pathologist Richard Shepherd, who carried out the third of three autopsies on Williams, said it appeared certain that the spy climbed into the bag voluntarily.
It was more likely that Williams "was alive when he entered the bag than that he was dead," he told the hearing.