A team of investigators, with the support of specialist police teams, is working to understand the circumstances of the death, Detective Inspector Daryl Smith said.
The investigation team had received a large amount of support from the public.
Detectives are still seeking sightings of two vehicles on Kopu-Hikuai Rd on Wednesday night between 6pm and 7.30pm - a dark green 1997 Jaguar xJ6 Saloon and a silver 2003 Mazda Bounty double cab ute.
It is understood the green Jaguar belonged to Williams.
The man accused of the murder is also charged with unlawful possession of a firearm.
At his first court appearance he was supported in court by family members. The accused will reappear in the High Court at Hamilton on August 25.
