The British women's parents, Ian and Jacqueline Clarke from Northumberland, and Ray and Jillian Walters from Wales, gasped as the verdicts on Australia's most gruesome serial killings, the "backpacker murders", were pronounced in the New South Wales Supreme Court after the jury of seven men and four women had deliberated for more than four days. An eighth man on the jury withdrew after he received a death threat from a man who said: "If you find him guilty you're dead."
The Clarkes, the Walters and the families of the other backpacker victims, three from Germany and two from Australia, had sat through the trial since it began in March, during which the details of their children's violent deaths in the forest were recounted in chilling detail.
Yet, as they prepared to fly back to Britain yesterday, the Clarkes and Walters were left with the knowledge that Milat was almost certainly not the sole killer. Mr Justice David Hunt, the presiding judge, accepted the prosecution's case that Milat probably acted with an accomplice. Sentencing, the judge said the case against Milat was overwhelming, and that any other verdict "would have flown in the face of reality".
The judge added: "The jury's verdicts mean that the prisoner was involved, either alone or in company, in a criminal enterprise to pick [the backpackers] up and then to murder them all. In my view, it is inevitable that the prisoner was not alone in that criminal enterprise."
Mr Clarke said he found disturbing the prospect that another killer could be still on the loose. "If it's the case that another murderer hasn't been caught, we have the awful prospect that there is someone else on the streets who should not be on the streets," he said. "There is a clear message to backpackers that it isn't as safe as they think it is."
Mr Clarke urged other backpackers not to be deterred by what happened to his daughter. "Our kids were desperately unlucky," he said. "Ninety- nine per cent of backpackers have a wonderful time. Keep coming, but be careful."
The question now is whether police will declare the case closed or continue their search for a second killer. Suspicion still centres on the Milat family. Ivan Milat is the fifth oldest in a family of 14, of Yugoslav origin, some of whose members live in the suburbs on the south-west outskirts of Sydney, near where the backpackers were picked up as they hitched lifts along the Hume Highway, the main trunk road linking Sydney and Melbourne.
During the trial, Terry Martin, Milat's barrister, argued that Milat was not the killer, but that whoever it was "must be in the Milat family or so closely related to it that it doesn't much matter". He suggested that it was more likely to be Milat's two younger brothers, Richard, 40, a labourer, or Walter, 44, a building tradesman, or both of them. The pair denied being involved.
The Milat brothers are gun-lovers. Between them, they amassed an arsenal of weapons and crates of ammunition.
Onions became a vital witness when he identified Milat as the man who picked him up then threatened him with a gun on the Hume Highway in January 1990. In the end, though, most of the circumstantial evidence that police uncovered pointed to Milat. The bolt and trigger assembly of a Ruger 10/22 semi-automatic rife, used to shoot Miss Clarke and one of the German victims, was found hidden in a wall cavity of Milat's house.
Lying around the same house, police also found a water bottle, a cooking set and a sleeping bag that belonged to Simone Schmidl, another German victim. Perhaps the most telling evidence was found when police raided Milat's garage and arrested him in May 1994: a pillow case containing sash cords, similar to those with which the bodies in the forest had been tied up, and one of them stained with the blood of Ms Clarke.
Miss Clarke, 21, and Miss Walters, 22, both nannies, became travelling companions in Australia in 1992. Both kept in touch with their parents in Britain by phone. The calls stopped after 18 April 1992, when they left a backpackers' hostel in inner Sydney to hitch-hike south. Their bodies were found in the Belanglo forest five months later. Miss Clarke had been shot 10 times in the head and Miss Walters had been stabbed 14 times.
Milat's other victims met their deaths in a similar manner: being picked up on the Hume Highway, overpowered, driven into the forest and then disposed of, probably after being tortured. Australians James Gibson and Deborah Everist, both 19, were stabbed. Miss Schmidl, 21, was stabbed. German Anja Habschied, 20, was decapitated and her boyfriend, Gabor Neugebauer, 21, was strangled and shot.
Mr Justice Hunt was apparently shaken by the case. Before pronouncing sentence yesterday, his voice faltered as he said: "They would obviously have been absolutely terrified and death is unlikely to have been swiftly applied. It is perhaps possible to imagine a worse case, but these murders must unhesitatingly be labelled as falling within the worse class of case."