A lakeside murder, in which three teenagers on a camping holiday were bludgeoned with rocks and stabbed in their tent, has haunted tranquil Finland for 45 years, spawning books, conspiracy theories and even the name of a rock band.

　　This week a court in the small town of Espoo will hear evidence that the only survivor of the attack, a retired bus driver who is now 63, killed his camping companions in a fit of jealousy because he wanted to have sex with one of the girls.

　　In a case that has prompted frenzied media interest, Nils Gustafsson denies he killed two 15-year-old girls and his 18-year-old best friend and claims - as he has done for 45 years - that he cannot remember what happened on the night of 4 June 1960.

　　On Thursday prosecutors and the defence visited the murder site at Lake Bodom, 20 kilometres west of Helsinki. To visitors, the spot where the four youngsters pitched their tent looks like an idyllic Nordic bay ringed with birch trees shimmering in the midnight sun. But every Finn associates the spot with the most vicious killing in the country's history. And not everyone is convinced - despite new forensic evidence analysed with British help - of Gustafsson's guilt.

　　'Three generations of children have grown up being told not to stay out late for fear of the Bodom murderer,' said Espoo shopkeeper Anna Pirisjoki. 'We feel that, if it really was Gustafsson, the police would have charged him long ago.'

　　Gustafsson, who is married with two grown-up children, had until last May been absolved of guilt because he appeared to have suffered serious injuries. Police now claim the broken jaw he sustained was the result of a fight with his best friend, Seppo Boisman, whom he later killed with rocks and a knife, along with his girlfriend, Irmeli Bjorklund, and her friend, Tuulikki Maki, both 15.

　　Police believe Gustafsson arranged the crime scene, removed Bjorklund's trousers and inflicted stab wounds on himself to give the impression of a frenzied sex attack by a mad knifeman. They say a key piece of prosecution evidence is Gustafsson's shoes, on which British forensic scientists earlier this year found traces of the victims' blood.

　　Many people in Espoo believe the real killer was a kiosk attendant at the beauty spot, who killed himself in 1972 and confessed to the triple murder in a suicide note. But police say he was sleeping with his wife on the night of the killing.

　　In hearings last week Gustafsson appeared passive as he heard written witness statements and accounts from birdwatchers and anglers who were as young as 11 in 1960. Among them was a woman who was camping nearby with friends on the night of the murders and who did not come forward until she was interviewed for a television documentary last year.

　　She claims Gustafsson and Boisman had visited her tent during the evening of the murders and that Gustafsson had been drunk and behaved aggressively. In defence evidence this week

　　Gustafsson's lawyer, Riitta Leppiniemi, will argue that he was in the tent when an outsider stabbed the four campers through the fabric. She will argue that traces of Gustafsson's blood inside the tent confirm that he, too, was a victim.

　　Leppiniemi said: 'Gustafsson remembers certain things clearly such as the arrival at the campsite. He also remembers clearly that the party did not visit another tent. The woman claiming this has kept quiet for 45 years. Also, Bjorklund's diary does not mention the visit.'

　　The lawyer claims Gustafsson had no motive, and that a number of items disappeared from the murder scene and were never found. The case is due to continue until Friday.