Police have found the Nissan Terrano they believe was involved in the murder of a Hamilton man at McLaren Falls.

Detective Inspector Graham Pitkethley said they were now seeking sightings of the car between Hamilton and the falls around the time Mitchell Paterson was killed.

He said every day police were getting closer to making arrests on three gang-related murders in the Waikato.

Organised crime and gangs were an ongoing problem in the Waikato and across the country, Detective Inspector Graham Pitkethley said at a press conference this afternoon.

When Robert Nelson was shot dead in the house of his partner Kahlee Marfell, protecting her from a flurry of bullets, people wondered if perhaps the shooting was connected to Noda's death.

It occurred a week after Noda died so was it a retaliation killing?

Police wouldn't say but those close to 'Griff' all but dismissed the suggestion.

Patterson confirmed at the time that Nelson was shot after a "number of shots" were fired in the house but little other detail was given.

Marfell lived at the Matthews Cres, Melville, home with her senior Mongrel Mob gang member dad Mark 'Griff' Griffiths.

He was also home but was able to stay safe in his bedroom which was further down the hallway.

His 17-year-old nephew didn't fare as well though. He got shot four times, a relative told the Herald, two in the torso, one in the head and the other in the shoulder, after three gunmen knocked at the front door asking if "Mark" was home.

Murder victim Robert Nelson, 23, with his partner Kahlee Marfell.

The teen is still fighting for his life in Auckland Hospital.

It was 1am when they knocked at the door. Not exactly visiting hours.

The terror amongst all those inside the converted five bedroom home must have been palpable.

Marfell was shot in the side of the upper thigh. The gunman either used a high powered rifle or he got close as the bullet went through one thigh, coming to rest in the other.

A couple of days after being shot, Marfell posted a Facebook live video that she was doing okay from her Waikato Hospital bed.

She was discharged from hospital last week.

Nelson's sister, Erin, also spoke out at the time saying he was in the wrong place at the wrong time and he wasn't involved in any gang.

If the relative's comment that the gunmen had asked for "Mark" at the door is true, Erin Nelson is right.

A source believed neither of the deaths were connected.

There was a fire at the Melville house late Friday night. It's understood there wasn't a lot of damage as it burnt out but it is being treated as suspicious.

Police had been unusually quiet about the shooting for a week, despite a third person, Mitchell Paterson, being found dead at McLaren Falls on Friday morning.

Mitchell Paterson was found dead in water below the McLaren Falls Bridge on Friday morning.

He was found in a body of water under the bridge and now police are seeking sightings of suspicious activity, either by vehicles or people, from the day before.

Police today said he was killed after a "physical assault".

In particular, they want to hear from people who saw a light coloured SUV, travelling either in convoy or singular, between 5.30am and 7am that morning.

Since his death, the Hamilton community has been on edge, and again people wondered if it was that retaliatory step that was being thrown around after, likely another gang, targeted a senior Mongrel Mob member.

The police Eagle helicopter has been more prolific in Hamilton's skies in recent days, while the armed offenders squad has been seen in neighbourhoods.

There have been three arrests, although only one that is allegedly directly linked to a murder.

James Lee Green is in custody charged with being an accessory after the fact of murder by helping another man - who the Herald has chosen not to name - dispose of Paterson's body.

With still no word from police on Monday and from comments made by residents on social media, anxiety levels were rising in the community.

Waikato police Superintendent Bruce Bird finally responded to requests for comment on Tuesday, confirming the deaths didn't appear to be linked but they were all gang-related.

"Across the investigations there are a number of people assisting Police and there are also persons of interest.

"Investigations to date indicate that these people have significant links with criminal gangs."

"As with all investigations we are keeping an open mind on whether the homicides are linked, however inquiries to date lead us to believe the three deaths were targeted individual acts within the gang community," he said.

But which gangs are involved and why? Were they all gang members or some? Were the deaths drug related? How many more lives will be lost before this is all sorted?

The police were this afternoon holding a press conference where more questions would hopefully be answered.

Anyone with information about any of the homicides is urged to phone the investigation team at Hamilton police on 07 858 6200.

Alternatively, information can be left anonymously with Crimestoppers on 0800 555 111.