"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 now. 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 both 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 1, 2013.
"The bottom line is that if you know something, we need to hear from you."
Paeroa businessman Jordan Voudouris, 55, was killed in the early hours of June 18, 2012 with his body being found behind his premises, Mykonos Pizza and Pasta Restaurant in Belmont Rd.
"A post-mortem determined Mr Voudouris had been fatally shot."
Anyone with any information on the identity of the offender or offenders or other information that could assist is asked to contact the Operation Olive enquiry team on 0508 Paeroa (723762) or their nearest police station.