The tourist shot dead in Raglan this morning has been identified as 33-year-old surfer Sean McKinnon, a "lovable, knockabout Aussie guy".
A homicide investigation was launched this afternoon, and Waikato police are seeking a male gunman, Detective Inspector Graham Pitkethley confirmed today.
Mr McKinnon, who grew up in Warrnambool in south-west Victoria, was holidaying in New Zealand with his Canadian fiancée.
The couple were sleeping in a campervan in a carpark at Te Toto Gorge in Raglan early this morning when a man woke them up wanting the keys, police said.
The 33-year-old was then shot "more than once", with his Canadian fiancée managing to flee to a nearby address where she called police.
Police said they were called to "a serious incident" at 3.20am on Whaanga Road in Raglan.
Friend Julian Smith told AAP Mr McKinnon loved to surf big waves along the Victorian coast.
"He was a lovable, knockabout Aussie guy, loved his surfing," Mr Smith said.
"He charged big waves."
Mr McKinnon's sister Emmeline McKinnon told News Corp she feels "sheer helplessness".
"It's a horrible thought to know he was alone when he died," she said.
"He would always tell you he loved you and would give you a hug."
Ms McKinnon told News Corp the killer had devastated their family.
"You took away someone deeply loved and treasured," she said.
Corangamite shire councillor Simon Illingworth told the Warrnambool Standard he had known Mr McKinnon for years through the local surfing community.
"He's just an awesome bloke, cruisy, honest, give you the shirt off his back sort of bloke," he said.
"Seanny Mac was always a legend. He would do somersaults off the Port Campbell pier with the kids. He always had time for everyone."
Investigators in New Zealand said today they are working through a number of leads about people of interest after tip-offs from members of the public this morning.
Mr Pitkethley said someone would have information about the attack and implored them to come forward to police.
“This is a random attack by at this stage what we can attribute to a sole offender but due to the circumstances of the attack it’s likely that he has confided in members of community,” Mr Pitkethley said.
Police want to speak to anyone who saw the White 2017 Toyota Hiace ZL registration KWF362 travelling from from Whaanga Road to Gordonton Road between 2am and 8am this morning.
Anyone with information is asked to contact Hamilton Police on 07 858 6200 or anonymously via Crimestoppers on 0800 555 111.
A general arming order is in place for Waikato police as a precautionary measure, but will be assessed later today, Mr Pitkethley said.
AAP contributed to this report.