A man has been charged with dangerous driving causing death, after a fatal accident on Sunday.
54-year-old James Gregory Nelson died in the collision in Ohingaiti, north of Hunterville, on November 12.
Although charges have been laid against one man in relation to the death, police say they still need to speak to witnesses.
Detectives are particularly interested in any sightings of three motorbikes possibly travelling together southbound on State Highway 1.
Police believe the motorcyclists would have been on the highway between Taupo and Bulls between 5pm and 6.30pm on Sunday, November 12.
Anyone with information is asked to contact Detective Karl Reyland of Whanganui Police, on 06 349 0600.
Emergency services were called to the crash on Sunday after a motorcycle and several other vehicles crashed around 6.30pm.
At the time police said three others were also taken to hospital with moderate to serious injuries.