Malmelin was born 1872 in Espoo as the illegitimate child of Helena Gustava Malmelin, a maid at a Lahnuscroft.[2][3] As an adult, Malmelin became a farmworker at the Simola croft in Klaukkala, a village in the southern part of the Nurmijärvi municipality.[4] The tenant there was Johan Ezekiel Aspelin. Malmelin began dating Edla, the crofter's daughter,[4] but when she would not become his wife, he killed everyone on the croft with an axe on 10 May 1899.[5] Three of the victims were women and two were children. Malmelin was arrested a couple of weeks later.[6]
Malmelin was sentenced to life imprisonment by the Turku Court of Appeal. The case was the subject of a broadside ballad, and Nurmijärvi parish became popularly known as Murhajärvi (which literally means "murder lake"). Malmelin served 13 years of his sentence before being pardoned by Nicholas II in 1912.[7] The later events of Malmelin's life remain unknown. He died to a long-term illness in 1944, aged 72, in Riipilä, Vantaa.[5][8]
