The hunt for the killer of roadworker George Taiaroa is widening with police questioning people as far away as Auckland.
Police are stopping traffic and questioning motorists in the hunt for Mr Taiaroa's killer, a week after the 67-year-old road worker was gunned down on Tram Road, Kinleith about 25kmsouth of Tokoroa.
Police have checkpoints set up at different locations throughout the South Waikato as they seek more clues for the whereabouts of a blue Jeep Cherokee that was last seen on Link Road between Magakino and Benneydale not long after Mr Taiaroa was killed.
Detective inspector Tim Anderson said police were seeking any information from people who may have seen the vehicle or any other information that may aid their inquiry.
He could not confirm how old the vehicle was but confirmed earlier reports that it was probably missing one of its number plates.
Mr Anderson said the vehicle could be hidden locally and he asked people to be vigilant.
He said the eagle helicopter had been in use to help with the search for the vehicle.
"We had a lady call us the other day about a submerged blue vehicle," he said. "We tracked it down and it was not the vehicle...this is a difficult place to search."
Mr Anderson said the investigation was proving difficult and frustrating.
"There's no doubt about that, it's frustrating in the sense we haven't resolved it yet."
"We still think there's a number of opportunities for the public of the community of the greater North Island to help us resolve this."
He said police had spoken with Mr Taiaroa's family to learn more about his background.