[1][2] The killings took place on 5 June 1976 in a weekend house named "Waldeggli" that stood on a meadow by the forest edge near Seewen, Solothurn, Switzerland.
The criminal investigation department followed many leads and systematically searched for owners of Winchester rifles.
However, there was little hope of finding the culprit until the autumn of 1996, when a Winchester rifle was found hidden in the walls of a kitchen of a house belonging to a woman named Doser.
The gun, which belonged to Carl Doser, was an Italian Winchester imitation with a short barrel.
[5] He had earlier been interviewed by the police, but he lied, telling them he had sold the gun on the flea market.
The shop assistant at R. Mayer AG recalled that the man who bought the ammunition had asked for two packages of Kal.