Lake Bodom murders

The Lake Bodom murders is an unsolved homicide case in which three teenage campers were killed and another seriously injured in Finland. The case is one of the most notorious crimes in modern Finnish history.

Sometime between 4:00 a.m. and 6:00 a.m. (EET) on 5 June 1960, at Lake Bodom in Espoo, Uusimaa, Maila Irmeli Björklund (15), Anja Tuulikki Mäki (15), and Seppo Boisman (18) were killed by stabbing and blunt-force trauma to their heads while sleeping inside a tent. The fourth youth, Nils Gustafsson, then-aged 18, was found outside the tent with broken facial bones and stab wounds.

Despite extensive investigations, the perpetrator was never identified and various theories on the killer's identity have been presented over the years. Gustafsson was unexpectedly arrested on suspicion of committing the murders in 2004, but he was found not guilty the following year. Provided by Wikipedia