Anaru Moana disappeared from the Canterbury town of Waimate late last year.
The last person to report seeing the 37-year-old was his niece on the morning of December 20. He was reported missing three days later after he failed to attend his mother’s funeral.
Divers were expected to begin searching waterways in Waitaki today, close to where a silver Subaru was found burnt out two days after Mr Moana's disappearance.
In September, police appealed for members of the public to come forward if they had seen the Subaru in the vicinity of Duntroon or Blacks Point on the evening of December 20 or the early hours of December 21.
The burnt-out car was later discovered at the Waihao River layby off State Highway 1.
Detective Inspector Joel Syme said good progress had been made by the investigation team in identifying those responsible for Mr Moana's death.
“Police remain committed to holding to account the person or persons responsible for Anaru’s death We are also working hard to locate his body so we can return him to his whanau.
“We continue to urge anyone with information to contact police, or alternatively contact Crime Stoppers anonymously on 0800 555 111."