The handgun the police say a man used to take a woman hostage in a hotel in the Taranaki town of Opunake has still not been found.
Police expect the reconstruction of the 12 hour siege which led to the man being shot and killed could take some days to carry out.
Anthony Ratahi, 46, from Stratford, was killed by a single shot outside the Headlands Hotel where he took his former girlfriend hostage on Friday night.
Thirty officers are working on the investigation.
Acting District Commander, Central District, Inspector Pat Handcock, says Mr Ratahi was shot and killed after he had refused to surrender and a police dog had been set on him.
He says the police have quite a significant area to search and the scene examination, which started on Sunday morning, is expected to continue for the next two to three days.
Mr Handcock says the Headlands Hotel is a large complex with three floors and Mr Ratahi and his hostage were in the premises for around 12 hours.
He says every part of that property will be subject to the scene examination.
Mr Handcock says a knife was found next to Anthony Ratahi's body and the police can't discount finding other weapons.
Police are holding three investigations into the incident - one focussing on the actions of the dead man, one on the actions of the police and a third on police procedures and guidelines.
The Independent Police Conduct Authority is also investigating the incident.
A relative of Mr Ratahi says he would have almost certainly been on drugs throughout the siege.
The relative, who did not wish to be named, says he was released from prison just before the incident, for assaulting the same woman earlier in the year.
She says he was a calm and loving man, but was an avid drug user and could have been on a mix of any number of drugs during the siege.
Tangi to be held
A date for a tangi for Mr Ratahi will be decided when the police release his body.
It will be held in either Opunake or Wellington, where he lived for a number of years.