my granddad fished Lake Bodom and refused to camp on the east shore his whole life

Not a repost, this is family. Finnish side. Lake Bodom, near Espoo, Finland. June 1960. Four teenagers camping by the lake. Sometime between 4 and 6 in the morning something/someone attacks the tent. Three dead — stabbed and beaten through the canvas. One survivor, Nils Gustafsson, badly hurt, foun……