Police say they have identified a "main suspect" in relation to the murder of George Taiaroa in Atiamuri last month.
A vehicle believed to have been involved in the fatal shooting of the stop-go sign operator has also been seized and is currently being forensically examined.
Detective Inspector Tim Anderson said today police "believe we are closer to the motive behind the cold-blooded murder".
"We do have a main suspect in relation to this investigation and we are also working on the possibility that he is being protected or actively assisted by others," Mr Anderson said.
Mr Anderson said he would not comment on "individuals of interest to this investigation".
He said the investigative team of more than 30 officers had "covered a lot of ground and that has included the preparation and execution of a number of search warrants in both the Bay of Plenty and Taranaki".
The car had been seized from the Bay of Plenty, he said.
"I will not be drawn on the specifics of those warrants and whether or not any of those remain pertinent to the ongoing inquiry," Mr Anderson said.
"What I am able to say is that we have recently seized a vehicle that we believe was involved on the day of the murder and we also believe we are closer to the motive behind the cold-blooded murder."
Mr Taiaroa was shot as he operated a stop-go sign on Tram Rd at Atiamuri March 19.
"Just because we have reached a turning point in the investigation, that doesn't mean we don't still need information from the public," Mr Anderson said.
"They have been crucial in getting us this far and their assistance remains and they can still make a significant difference.
"We remain particularly interested in the movements of a late 90s, dark blue Jeep Cherokee on the day of the murder and the days that followed.
"We also remain particularly interested in sightings of this vehicle in and around south Taranaki, Taumarunui, Benneydale and Rotorua."
Anyone with information should call the investigation team on 0800 Kingswood (0800 546 479) or Crimestoppers on 0800 555111.
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