An Italian judge has ruled that three men detained over a cable car crash that killed 14 people in northern Italy can leave prison, with one of them being placed under house arrest. In the crash a week ago, a gondola on the cable connecting the Lake Maggiore resort town of Stresa to a nearby mountain plunged to the ground, killing all aboard apart from a five-year-old Israeli boy who remains in hospital. Prosecutors in the city of Verbania have opened an investigation into suspected involuntary manslaughter and negligence. Police arrested the three men on Wednesday. The judge ruled there were no grounds for keeping them in jail because they could not run away and there was no risk of evidence being tampered with, according to Italian media. Prosecutors allege that the three men – the owner of the cable-car company and two employees – were aware of technical problems. They said in a legal filing that the three had deliberately placed fork-shaped clamps on the emergency brakes to avoid them being constantly activated. “I’m aware of the mistake I made leaving the clamps on,” Gabriele Tadini told the prosecutors, according to the official transcript of his interview quoted by Sunday’s Corriere della Sera newspaper. Tadini was in charge of setting the lift in motion, which he did on 23 May just a few hours before the crash. Tadini has been placed under house arrest. His lawyer, Marcello Perillo, said he had not requested his client’s release after his admission. “There is no denying the issue of the clasps, for that he will have to face consequences,” Perillo said, adding that the extent to which the other two men had been informed of Tadini’s actions was still to be established. “There is no proof at present they were also responsible. They are people who should have known, but it’s not clear if they did,” he said. Enrico Perocchio, the engineer employed by the company in charge of safety checks on the cable car, said as he left Verbania prison on Saturday night that he had no idea the brakes had been blocked. “I’ve got 21 years of experience with lifts that use cables, I know that’s something you don’t ever, ever do,” Perocchio said, according to the website of La Repubblica. Perocchio and Luigi Nerini, the owner of the company that operates the lift, have been freed pending the outcome of the investigation. In ordering their release, the judge, Donatella Banci Buonamici, wrote that there was “a complete lack of proof” against Nerini and Perocchio and the prosecutors’ request to keep them in jail was based on “mere suppositions”. Nerini’s lawyer, Pasquale Pantano, told reporters on Saturday night that his release was welcome news, but it was key to now find out who was responsible for the disaster.