An Australian man was found guilty on Thursday of killing two women in Perth in the mid-1990s, but acquitted of a third death, marking a partial close to one of the country’s highest-profile and longest-running unsolved murder cases. Former telecoms technician Bradley Edwards, 51, was found guilty of murdering child-care worker Jane Rimmer, 23, and lawyer Ciara Glennon, 27, in 1996 and 1997 after abducting them from the downtown entertainment district of Claremont.

Supreme Court Justice Stephen Hall acquitted Edwards of killing Sarah Spiers, the first woman to disappear but whose body has never been found, saying that although it was possible or even probable Edwards was the killer, there was not enough evidence to convict him. “Bradley Edwards’ crimes spanned a decade of terror starting with violent assault that escalated to the murder of young women,” Western Australian police commissioner Chris Dawson told reporters. “It is indeed a dark period in our history.”

Both women were found in bushland with their throats cut, with other wounds from trying to defend themselves. Advances in forensic science allowed police to identify fragments of Edwards’ DNA from under Glennon’s fingernails before his arrest in 2016.

Blue polyester fibres that were found on both women’s bodies, as well as the shorts of a 17-year-old girl Edwards admitted raping at a cemetery in 1995, matched the fibres used in Edwards’ uniform, a colour manufactured solely for his company. Karl O’Callaghan, police commissioner at the time of Edwards’ arrest, said the finding was “an enormous relief.”

“I guess somewhat mixed emotions too, because only two convictions were recorded,” he said. State Premier Mark McGowan appealed for Edwards to reveal the location of Spiers’ body.

“This is to Mr Edwards: If you know where Sarah Spiers is, can you please tell us… Can you please provide some closure to the Spiers family to let them know where their daughter is?”