A $50,000 reward was posted in an effort to progress a conclusion to the murder of Paeroa pizza man Jordan Voudouris.
Waikato police investigating the June murder of the business man believe the introduction of a reward may prompt those holding key pieces of information to come forward.
Detective Sergeant Glenn Tinsley said with Operation Olive, the investigation into the murder of Mr Voudouris, into its eighth month, the inquiry team still believed someone could hold information that could solve the mystery.
The Police Commissioner authorised a reward of up to $50,000 would be paid for material information or evidence, which lead to the identity and conviction of any person or persons responsible for the death of Mr Voudouris.
Immunity from prosecution will be considered for any accomplice, not being a principal offender responsible for his death, who is the first to give such information or evidence.
"While police did not often offer rewards we believe a reward may be just the incentive needed to get someone to come forward who hasn't spoken to investigators, "said Mr Tinsley.
"Often in cases such as this people's loyalties change as time goes on and we urge anyone who may have information not made available to us earlier to come forward. Similarly, there may be someone with information who has held back hoping the murder would be solved without them having to get involved."
Mr Tinsley said it is important for Mr Voudouris' family and for the wider Paeroa community that anyone with information comes forward.
"The Commissioner of Police will determine the amount of the reward and will, if necessary, apportion payment where there is more than one claimant and the reward offer shall remain in force until July 01.
Mr Voudouris, 55, was killed in the early hours of Monday, June 18. His body was found behind his premises, Mykonos Pizza and Pasta Restaurant.
A post-mortem determined Mr Voudouris had been fatally shot.
Anyone with any information on the identity of the offender, offenders or other information that could assist can contact the Operation Olive inquiry team on 0508 Paeroa (723762) or their nearest police station.