Karl Emil Malmelin (16 January 1872 – ?) was a Finnish farmworker and mass murderer.
Malmelin was born 1872 in Espoo as an illegitimate child to Helena Gustava Malmelin, the maid of Lahnus croft.
As an adult, Malmelin ended up in the Simola croft in Klaukkala, Nurmijärvi, to serve as a farmworker.
The croft was hosted by Johan Ezekiel Aspelin.
At that time, Malmelin had begun dating Edla, the croft's daughter, but when she had not consented to be Malmelin's wife, wrathful Malmelin killed the entire croft's people in retaliation on May 10, 1899, using an axe as a weapon.
Three of the victims were women and two were children.
Malmelin was arrested a couple of weeks later.Malmelin was sentenced to life imprisonment by the Turku Court of Appeal.
The murder case was also broadside balladed and Nurmijärvi parish received a bad reputation as Murhajärvi (literally means "murder lake").
Malmelin spent 13 years of his life in prison until he was pardoned by Nicholas II in 1912.
The later events of Malmelin's life have remained unknown.Nowadays, Malmelin is still one of the worst axe murderers in Finnish history, along with Toivo Koljonen.