The killing of a man in Tabibuga in the new Papua New Guinea province of Jiwaka is the first serious incident since campaigning for the June election began.
Two other people have serious injuries.
The newspaper, The National, reports the Jiwaka police commander, Superintendent Simon Nigi, as saying supporters of two candidates - Mai Dop and Clement Kupul - attacked each other while nomination formalities were being processed last Wednesday.
A youth who was a Kupul supporter later died from knife injuries.
Additional Police have since been deployed to the area.