The Manawatu police believe a house in Woodville has been deliberately set alight because a man was killed there earlier this year.
The house in Ormond St was extensively damaged in the fire, which started at about 1am this morning.
The body of 49-year-old James Whatuira was found in the house on 4 January.
Detective Sergeant Johnny Oram said while a link between Mr Whatuira's death and the suspected arson had not yet been established, the police considered it a strong possibility.