Police are trying to contact a person who handed in a knife that may have been the weapon used in the New Year's Day murder of Murray Wilkinson.
The security guard at the Waihi Beach crime scene who was handed the knife on Thursday failed to record the person's details, Detective Inspector Chris Page said.
Police have appealed for the member of the public who handed in the knife to contact investigators.
"It is not known if this knife has anything to do with the incident but for the investigation it is very important for us to know where the knife was found, when and by who," Mr Page said today.
"These are the sorts of details that help us to determine what is and is not relevant in cases such as this.